From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tom Lendacky Subject: Re: [PATCH net-next 08/12] amd-xgbe: Add ethtool show/set channels support Date: Tue, 22 May 2018 10:37:57 -0500 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: netdev@vger.kernel.org, David Miller To: Edward Cree , Jakub Kicinski Return-path: Received: from mail-co1nam03on0050.outbound.protection.outlook.com ([104.47.40.50]:12612 "EHLO NAM03-CO1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751272AbeEVPiD (ORCPT ); Tue, 22 May 2018 11:38:03 -0400 In-Reply-To: Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: On 5/22/2018 8:29 AM, Edward Cree wrote: > 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. Ok, another vote on changing the logic. I'll update it and submit a v2. Thanks, Tom > > -Ed >