From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: <michael.qiu@intel.com> Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by dpdk.org (Postfix) with ESMTP id 27D358D28 for <dev@dpdk.org>; Tue, 2 Feb 2016 03:57:31 +0100 (CET) Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga104.fm.intel.com with ESMTP; 01 Feb 2016 18:57:30 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.22,383,1449561600"; d="scan'208";a="874648138" Received: from fmsmsx105.amr.corp.intel.com ([10.18.124.203]) by orsmga001.jf.intel.com with ESMTP; 01 Feb 2016 18:57:31 -0800 Received: from fmsmsx111.amr.corp.intel.com (10.18.116.5) by FMSMSX105.amr.corp.intel.com (10.18.124.203) with Microsoft SMTP Server (TLS) id 14.3.248.2; Mon, 1 Feb 2016 18:57:29 -0800 Received: from shsmsx104.ccr.corp.intel.com (10.239.110.15) by fmsmsx111.amr.corp.intel.com (10.18.116.5) with Microsoft SMTP Server (TLS) id 14.3.248.2; Mon, 1 Feb 2016 18:57:29 -0800 Received: from shsmsx101.ccr.corp.intel.com ([169.254.1.215]) by SHSMSX104.ccr.corp.intel.com ([169.254.5.117]) with mapi id 14.03.0248.002; Tue, 2 Feb 2016 10:57:27 +0800 From: "Qiu, Michael" <michael.qiu@intel.com> To: "Zhang, Helin" <helin.zhang@intel.com>, "Lu, Wenzhuo" <wenzhuo.lu@intel.com>, "dev@dpdk.org" <dev@dpdk.org> Thread-Topic: [PATCH v2] ixgbe: Fix disable interrupt twice Thread-Index: AQHRWlokuxzst+DuYUqlXTIjOup9yQ== Date: Tue, 2 Feb 2016 02:57:26 +0000 Message-ID: <533710CFB86FA344BFBF2D6802E6028622F28B7B@SHSMSX101.ccr.corp.intel.com> References: <1454046700-20843-1-git-send-email-michael.qiu@intel.com> <1454047090-21274-1-git-send-email-michael.qiu@intel.com> <6A0DE07E22DDAD4C9103DF62FEBC0909034256DA@shsmsx102.ccr.corp.intel.com> <533710CFB86FA344BFBF2D6802E6028622F28091@SHSMSX101.ccr.corp.intel.com> <6A0DE07E22DDAD4C9103DF62FEBC0909034266D1@shsmsx102.ccr.corp.intel.com> <533710CFB86FA344BFBF2D6802E6028622F28A4D@SHSMSX101.ccr.corp.intel.com> <F35DEAC7BCE34641BA9FAC6BCA4A12E70A991744@SHSMSX104.ccr.corp.intel.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.239.127.40] Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] [PATCH v2] ixgbe: Fix disable interrupt twice X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK <dev.dpdk.org> List-Unsubscribe: <http://dpdk.org/ml/options/dev>, <mailto:dev-request@dpdk.org?subject=unsubscribe> List-Archive: <http://dpdk.org/ml/archives/dev/> List-Post: <mailto:dev@dpdk.org> List-Help: <mailto:dev-request@dpdk.org?subject=help> List-Subscribe: <http://dpdk.org/ml/listinfo/dev>, <mailto:dev-request@dpdk.org?subject=subscribe> X-List-Received-Date: Tue, 02 Feb 2016 02:57:31 -0000 On 2/2/2016 10:14 AM, Zhang, Helin wrote:=0A= >=0A= >> -----Original Message-----=0A= >> From: Qiu, Michael=0A= >> Sent: Tuesday, February 2, 2016 10:07 AM=0A= >> To: Lu, Wenzhuo; dev@dpdk.org=0A= >> Cc: Zhou, Danny; Liu, Yong; Liang, Cunming; Zhang, Helin=0A= >> Subject: Re: [PATCH v2] ixgbe: Fix disable interrupt twice=0A= >>=0A= >> [+cc helin]=0A= >>=0A= >> On 2/2/2016 9:03 AM, Lu, Wenzhuo wrote:=0A= >>> Hi Michael,=0A= >>>=0A= >>>> -----Original Message-----=0A= >>>> From: Qiu, Michael=0A= >>>> Sent: Monday, February 1, 2016 4:05 PM=0A= >>>> To: Lu, Wenzhuo; dev@dpdk.org=0A= >>>> Cc: Zhou, Danny; Liu, Yong; Liang, Cunming=0A= >>>> Subject: Re: [PATCH v2] ixgbe: Fix disable interrupt twice=0A= >>>>=0A= >>>> On 1/29/2016 4:07 PM, Lu, Wenzhuo wrote:=0A= >>>>> Hi Michael,=0A= >>>>>=0A= >>>>>> -----Original Message-----=0A= >>>>>> From: Qiu, Michael=0A= >>>>>> Sent: Friday, January 29, 2016 1:58 PM=0A= >>>>>> To: dev@dpdk.org=0A= >>>>>> Cc: Zhou, Danny; Liu, Yong; Liang, Cunming; Lu, Wenzhuo; Qiu,=0A= >>>>>> Michael=0A= >>>>>> Subject: [PATCH v2] ixgbe: Fix disable interrupt twice=0A= >>>>>>=0A= >>>>>> Currently, ixgbe vf and pf will disable interrupt twice in stop=0A= >>>>>> stage and uninit stage. It will cause an error:=0A= >>>>>>=0A= >>>>>> testpmd> quit=0A= >>>>>>=0A= >>>>>> Shutting down port 0...=0A= >>>>>> Stopping ports...=0A= >>>>>> Done=0A= >>>>>> Closing ports...=0A= >>>>>> EAL: Error disabling MSI-X interrupts for fd 26=0A= >>>>>> Done=0A= >>>>>>=0A= >>>>>> Becasue the interrupt already been disabled in stop stage.=0A= >>>>>> Since it is enabled in init stage, better remove from stop stage.=0A= >>>>> I'm afraid it=92s not a good idea to just remove the intr_disable fro= m=0A= >> dev_stop.=0A= >>>>> I think dev_stop have the chance to be used independently with=0A= >>>>> dev_unint. In=0A= >>>> this scenario, we still need intr_disable, right?=0A= >>>>> Maybe what we need is some check before we disable the intr:)=0A= >>>> Yes, indeed we need some check in disable intr, but it need=0A= >>>> additional fields in "struct rte_intr_handle", and it's much saft to= =0A= >>>> do so, but as I check i40e/fm10k code, only ixgbe disable it in dev_st= op().=0A= >>> I found fm10k doesn=92t enable intr in dev_start. So, I think it's OK. = But i40e=0A= >> enables intr in dev_start.=0A= >>> To my opinion, it's more like i40e misses the intr_disable in dev_stop.= =0A= >> I don't think i40e miss it, because it not the right please to disable i= nterrupt.=0A= >> because all interrupts are enabled in init stage.=0A= >>=0A= >> Actually, ixgbe enable the interrupt in init stage, but in dev_start, it= disable it=0A= >> first and re-enable, so it just the same with doing nothing about interr= upt.=0A= >>=0A= >> Just think below:=0A= >>=0A= >> 1. start the port.(interrupt already enabled in init stage, disable -->= =0A= >> re-enable)=0A= >> 2. stop the port.(disable interrupt)=0A= >> 3. start port again(Try to disable, but failed, already disabled)=0A= >>=0A= >> Would you think the code has issue?=0A= > [Zhang, Helin] in ixgbe PMD, it can be seen that uninit() calls dev_close= (),=0A= > which calls dev_stop(). So I think the disabling can be done only in dev_= stop().=0A= > All others can make use of dev_stop to disable the interrupt.=0A= =0A= As I said, if it is in dev_stop, it will has issue when dev_start -->=0A= dev_stop --> dev_start, this also could applied in i40e and fm10k. If=0A= you want to put it in dev_stop, better to remove enable interrupts in=0A= init stage, and only put it in dev_start.=0A= =0A= Thanks,=0A= Michael=0A= > Regards,=0A= > Helin=0A= >=0A= >> Thanks,=0A= >> Michael=0A= >>=0A= >>> Maybe we can follow fm10k's style.=0A= >>>=0A= >>>> On other hand, if we remove it in dev_stop, any side effect? In ixgbe= =0A= >>>> start, it will always disable it first and then re-enable it, so it's = safe.=0A= >>> I think you mean we can disable intr anyway even if it has been disable= d.=0A= >> Actually, we couldn't, DPDK call VFIO ioctl to kernel to disable interru= pts, and=0A= >> if we try disable twice, it will return and error.=0A= >> That's why I mean we need a flag to show the interrupts stats. If it alr= eady=0A= >> disabled, we do not need call in to kernel. just return and give a warni= ng=0A= >> message.=0A= >>=0A= >> Thanks,=0A= >> Michael=0A= >>=0A= >>> Sounds more like why we don't=0A= >>> need this patch :)=0A= >>>=0A= >>>> Thanks,=0A= >>>> Michael=0A= >=0A= =0A=