From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933227AbcIVKj2 (ORCPT ); Thu, 22 Sep 2016 06:39:28 -0400 Received: from mx2.suse.de ([195.135.220.15]:37178 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753122AbcIVKj1 (ORCPT ); Thu, 22 Sep 2016 06:39:27 -0400 Subject: Re: [Xen-devel] [PATCH resend] xen-netback: switch to threaded irq for control ring To: Paul Durrant , "xen-devel@lists.xenproject.org" , "netdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" References: <1474534964-15621-1-git-send-email-jgross@suse.com> <37d32749052f4ff887c5637671085389@AMSPEX02CL03.citrite.net> <2f3c7f1b-6a36-8aaa-e10a-41a1d2cf37d8@suse.com> <78418d2acd0446e8bbbd634377b9e263@AMSPEX02CL03.citrite.net> Cc: Wei Liu From: Juergen Gross X-Enigmail-Draft-Status: N1110 Message-ID: Date: Thu, 22 Sep 2016 12:39:24 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.3.0 MIME-Version: 1.0 In-Reply-To: <78418d2acd0446e8bbbd634377b9e263@AMSPEX02CL03.citrite.net> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 22/09/16 12:31, Paul Durrant wrote: >> -----Original Message----- >> From: Juergen Gross [mailto:jgross@suse.com] >> Sent: 22 September 2016 11:17 >> To: Paul Durrant ; xen-devel@lists.xenproject.org; >> netdev@vger.kernel.orga ; linux- >> kernel@vger.kernel.org >> Cc: Wei Liu >> Subject: Re: [Xen-devel] [PATCH resend] xen-netback: switch to threaded irq >> for control ring >> >> On 22/09/16 11:09, Paul Durrant wrote: >>>> -----Original Message----- >>>> From: Xen-devel [mailto:xen-devel-bounces@lists.xen.org] On Behalf Of >>>> Juergen Gross >>>> Sent: 22 September 2016 10:03 >>>> To: xen-devel@lists.xenproject.org; netdev@vger.kernel.orga; linux- >>>> kernel@vger.kernel.org >>>> Cc: Juergen Gross ; Wei Liu >>>> Subject: [Xen-devel] [PATCH resend] xen-netback: switch to threaded >>>> irq for control ring >>>> >>>> Instead of open coding it use the threaded irq mechanism in xen-netback. >>>> >>>> Signed-off-by: Juergen Gross >>> >>> How have you tested this change? >> >> Only compile-tested and loaded the module. As this feature isn't being used >> in linux netfront AFAIK it is not easily testable. OTOH the code modification is >> rather limited and I've used the threaded irq in the Xen scsiback driver >> myself, so I'm rather confident it will work. >> > > OK. How about doing the rx interrupt/task too so that it can be easily tested with a linux netfront? I'd like to, but this would require some more work. The rx kthread isn't activated by an event only, but by a timer, too. This isn't easy to map to the threaded irq framework. If, however, you are confident the timer isn't really necessary I'd be happy to provide a patch switching the rx task to the threaded irq, too. And to be honest: this wouldn't verify that the control ring related patch is really working. The mechanism itself _is_ working as it is already in use in xen-scsiback in a very similar environment. Juergen