From mboxrd@z Thu Jan 1 00:00:00 1970 From: Edward Cree Subject: Re: [PATCH net-next 08/12] amd-xgbe: Add ethtool show/set channels support Date: Tue, 22 May 2018 14:29:28 +0100 Message-ID: References: <20180521215818.8135.83100.stgit@tlendack-t1.amdoffice.net> <20180521215937.8135.63942.stgit@tlendack-t1.amdoffice.net> <20180521223542.3306664f@cakuba> <6346850c-ea57-ef4e-db0a-78d29fd360b3@amd.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Cc: , David Miller To: Tom Lendacky , Jakub Kicinski Return-path: Received: from dispatch1-us1.ppe-hosted.com ([148.163.129.52]:44702 "EHLO dispatch1-us1.ppe-hosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751421AbeEVN3e (ORCPT ); Tue, 22 May 2018 09:29:34 -0400 In-Reply-To: <6346850c-ea57-ef4e-db0a-78d29fd360b3@amd.com> Content-Language: en-GB Sender: netdev-owner@vger.kernel.org List-ID: On 22/05/18 14:24, Tom Lendacky wrote: > The amd-xgbe driver is not designed to allocate separate IRQs for Rx and > Tx. In general, there is one IRQ for a channel of which Tx and Rx are > shared. You can have more Tx channels than Rx channels or vice-versa, but > the min() of those numbers will be a combined Tx/Rx with the excess being > Tx or Rx only: e.g. combined 0 tx 8 rx 10 results in 8 combined channels > plus two Rx only channels. If you cannot allocate the channels requested by the user, surely the correct  thing is not to fudge it into something similar, but rather to return an  error from the ethtool set_channels() op. -Ed