From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by dpdk.org (Postfix) with ESMTP id DF4CF1B107 for ; Mon, 29 Apr 2019 18:51:29 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 29 Apr 2019 09:51:21 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,410,1549958400"; d="scan'208";a="165972201" Received: from fyigit-mobl.ger.corp.intel.com (HELO [10.237.221.33]) ([10.237.221.33]) by fmsmga002.fm.intel.com with ESMTP; 29 Apr 2019 09:51:10 -0700 To: Thomas Monjalon , "John W. Linville" , Xiaolong Ye , Qi Zhang , Shepard Siegel , Ed Czeck , John Miller , Igor Russkikh , Pavel Belous , Allain Legacy , Matt Peters , Ravi Kumar , Rasesh Mody , Shahed Shaikh , Ajit Khaparde , Somnath Kotur , Chas Williams , Rahul Lakkireddy , Hemant Agrawal , Shreyansh Jain , Wenzhuo Lu , Marcin Wojtas , Michal Krawczyk , Guy Tzalik , Evgeny Schemeilin , Gagandeep Singh , Pankaj Chauhan , John Daley , Hyong Youb Kim , Gaetan Rivet , Xiao Wang , Beilei Xing , Jingjing Wu , Qiming Yang , Konstantin Ananyev , Shijith Thotton , Srisivasubramanian Srinivasan , Matan Azrad , Shahaf Shuler , Yongseok Koh , Zyta Szpak , Liron Himi , Alan Winkowski , Tomasz Duszynski , Stephen Hemminger , "K. Y. Srinivasan" , Haiyang Zhang , Rastislav Cernay , Jan Remes , Alejandro Lucero , Tetsuya Mukawa , Jerin Jacob , Bruce Richardson , Andrew Rybchenko , Jasvinder Singh , Cristian Dumitrescu , Keith Wiles , Maciej Czekaj , Maxime Coquelin , Tiwei Bie , Zhihong Wang , Yong Wang , Anatoly Burakov Cc: dev@dpdk.org References: <30528485.5cHeq7CNxZ@xps> From: Ferruh Yigit Openpgp: preference=signencrypt Autocrypt: addr=ferruh.yigit@intel.com; prefer-encrypt=mutual; keydata= mQINBFXZCFABEADCujshBOAaqPZpwShdkzkyGpJ15lmxiSr3jVMqOtQS/sB3FYLT0/d3+bvy qbL9YnlbPyRvZfnP3pXiKwkRoR1RJwEo2BOf6hxdzTmLRtGtwWzI9MwrUPj6n/ldiD58VAGQ +iR1I/z9UBUN/ZMksElA2D7Jgg7vZ78iKwNnd+vLBD6I61kVrZ45Vjo3r+pPOByUBXOUlxp9 GWEKKIrJ4eogqkVNSixN16VYK7xR+5OUkBYUO+sE6etSxCr7BahMPKxH+XPlZZjKrxciaWQb +dElz3Ab4Opl+ZT/bK2huX+W+NJBEBVzjTkhjSTjcyRdxvS1gwWRuXqAml/sh+KQjPV1PPHF YK5LcqLkle+OKTCa82OvUb7cr+ALxATIZXQkgmn+zFT8UzSS3aiBBohg3BtbTIWy51jNlYdy ezUZ4UxKSsFuUTPt+JjHQBvF7WKbmNGS3fCid5Iag4tWOfZoqiCNzxApkVugltxoc6rG2TyX CmI2rP0mQ0GOsGXA3+3c1MCdQFzdIn/5tLBZyKy4F54UFo35eOX8/g7OaE+xrgY/4bZjpxC1 1pd66AAtKb3aNXpHvIfkVV6NYloo52H+FUE5ZDPNCGD0/btFGPWmWRmkPybzColTy7fmPaGz cBcEEqHK4T0aY4UJmE7Ylvg255Kz7s6wGZe6IR3N0cKNv++O7QARAQABtCVGZXJydWggWWln aXQgPGZlcnJ1aC55aWdpdEBpbnRlbC5jb20+iQJVBBMBAgA/AhsDBgsJCAcDAgYVCAIJCgsE FgIDAQIeAQIXgBYhBNI2U4dCLsKE45mBx/kz60PfE2EfBQJbughWBQkHwjOGAAoJEPkz60Pf E2Eft84QAIbKWqhgqRfoiw/BbXbA1+qm2o4UgkCRQ0yJgt9QsnbpOmPKydHH0ixCliNz1J8e mRXCkMini1bTpnzp7spOjQGLeAFkNFz6BMq8YF2mVWbGEDE9WgnAxZdi0eLY7ZQnHbE6AxKL SXmpe9INb6z3ztseFt7mqje/W/6DWYIMnH3Yz9KzxujFWDcq8UCAvPkxVQXLTMpauhFgYeEx Nub5HbvhxTfUkapLwRQsSd/HbywzqZ3s/bbYMjj5JO3tgMiM9g9HOjv1G2f1dQjHi5YQiTZl 1eIIqQ3pTic6ROaiZqNmQFXPsoOOFfXF8nN2zg8kl/sSdoXWHhama5hbwwtl1vdaygQYlmdK H2ueiFh/UvT3WG3waNv2eZiEbHV8Rk52Xyn2w1G90lV0fYC6Ket1Xjoch7kjwbx793Kz/RfQ rmBY8/S4DTGn3oq3dMdQY+b6+7VMUeLMMh2CXYO9ErkOq+qNTD1IY+cBAkXnaDbQfz0zbste ZGWH74FAZ9nCpDOqbRTrBL42aMGhfOWEyeA1x7+hl6JZfabBWAuf4nnCXuorKHzBXTrf7u7p fXsKQClWRW77PF1VmzrtKNVSytQAmlCWApQIw20AarFipXmVdIjHmJPU611WoyxZPb4JTOxx 5cv9B+nr/RIB+v5dcStyHCCwO1be7nBDdCgd4F6kTQPLuQINBFfWTL4BEACnNA29e8TarUsB L5n6eLZHXcFvVwNLVlirWOClHXf44o2KnN3ww+eBEmKVfEFo9MSuGDNHS8Zw1NiGMYxLIUgd U6gGrVVs/VrQWL82pbMk6jCj98N+BXIri+6K1z+AImz7ax7iF1kDgRAnFWU0znWWBgM2mM8Y gDjcxfXk4sCKnvf6Gjo08Ey5zmqx7dekAKU2EEp8Q1EJY3jbymLdZWRP4AFFMTS1rGMk0/tt v71NBg1GobCcbNfn9chK/jhqxYhAJqq86RdJQkt3/9x1U1Oq0vXCt4JVVHmkxePtUiuWTTt+ aYlUAsKYZsWvncExvw77x2ArYDmaK0yfjh37wp0lY7DOJHFxoyT8tyWZlLci/VMRG2Ja33xj 0CN4C1yBg+QDeV3QFxQo42iA/ykdXPUR3ezmsND3XKvVLTC4DNb3V/EZQ7jBj64+bEK0VW4G B31VP00ApNQvSoczsIOAKdk97RNbpmPw6q10ILIB+9T1xbnFYzshzGF17oC0/GENIHATx8vZ masOZoDiOZQpeneLgnFE9JfzhLTxv6wNZcc/HLXRQVTkDsQr8ERtkAoHCf1E5+b5Yr7pfnE4 YuhET746o25S53ELUYPIs49qoJsEJL34/oexMfPGyPIlrbufiNyty5jc/1MRwUlhJlJ5IOHy ZUa+6CLR7GdImusFkPJUJwARAQABiQI8BBgBAgAmAhsMFiEE0jZTh0IuwoTjmYHH+TPrQ98T YR8FAlu6CHAFCQXE7zIACgkQ+TPrQ98TYR9nXxAAqNBgkYNyGuWUuy0GwDQCbu3iiMyH1+D7 llafPcK4NYy1Z4AYuVwC9nmLaoj+ozdqS3ncRo57ncRsKEJC46nDJJZYZ5LSJVn63Y3NBF86 lxQAgjj2oyZEwaLKtKbAFsXL43jv1pUGgSvWwYtDwHITXXFQto9rZEuUDRFSx4sg9OR+Q6/6 LY+nQQ3OdHlBkflzYMPcWgDcvcTAO6yasLEUf7UcYoSWTyMYjLB4QuNlXzTswzGVMssJF/vo V8lD1eqqaSUWG3STF6GVLQOr1NLvN5+kUBiEStHFxBpgSCvYY9sNV8FS6N24CAWMBl+10W+D 2h1yiiP5dOdPcBDYKsgqDD91/sP0WdyMJkwdQJtD49f9f+lYloxHnSAxMleOpyscg1pldw+i mPaUY1bmIknLhhkqfMmjywQOXpac5LRMibAAYkcB8v7y3kwELnt8mhqqZy6LUsqcWygNbH/W K3GGt5tRpeIXeJ25x8gg5EBQ0Jnvp/IbBYQfPLtXH0Myq2QuAhk/1q2yEIbVjS+7iowEZNyE 56K63WBJxsJPB2mvmLgn98GqB4G6GufP1ndS0XDti/2K0o8rep9xoY/JDGi0n0L0tk9BHyoP Y7kaEpu7UyY3nVdRLe5H1/MnFG8hdJ97WqnPS0buYZlrbTV0nRFL/NI2VABl18vEEXvNQiO+ vM8= Message-ID: Date: Mon, 29 Apr 2019 17:51:09 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <30528485.5cHeq7CNxZ@xps> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Subject: Re: [dpdk-dev] CALL to eth PMD maintainers: complete closing of port X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 29 Apr 2019 16:51:30 -0000 On 4/18/2019 11:59 AM, Thomas Monjalon wrote: > Hi all, > > Since DPDK 18.11, the behaviour of the close operation is changed > if RTE_ETH_DEV_CLOSE_REMOVE is enabled in the driver: > port is released (i.e. totally freed and data erased) on close. > This new behaviour is enabled per driver for a migration period. > > Looking at the code, you can see these comments: > /* old behaviour: only free queue arrays */ > RTE_ETHDEV_LOG(DEBUG, "Port closing is using an old behaviour.\n" > "The driver %s should migrate to the new behaviour.\n", > /* new behaviour: send event + reset state + free all data */ > > You can find an advice in the commit: > http://git.dpdk.org/dpdk/commit/?id=23ea57a2a > " > When enabling RTE_ETH_DEV_CLOSE_REMOVE, > the PMD must free all its private resources for the port, > in its dev_close function. > It is advised to call the dev_close function in the remove function > in order to support removing a device without closing its ports. > " > > It would be great to complete this migration for the next LTS > version, which will be 19.11. > It means the work should be ideally finished during the summer. I would like to detail a little more what needs to be done, mainly for the sake of the discussion, please comment if something missing/wrong. There are two exit paths for driver: 1) Hotplug remove the device rte_dev_remove() OR rte_eal_hotplug_remove() 2) Application exit: rte_eth_dev_close() (1) can be called without ethdev stop and close functions called, so the path should cover those functions. And in the PMD entry point in this path is .remove() function. In this .remove() function PMD should: - stop forwarding - clean PMD private resources (dev_close() ? ) - clean ethdev generic resources (rte_eth_dev_release_port() ? ) - remove device resources, which already done by remove APIs (2) ethdev won't be usable after "rte_eth_dev_close()" and it should clear PMD private and ethdev generic resources. With RTE_ETH_DEV_CLOSE_REMOVE flag 'rte_eth_dev_close()' will free generic ethdev resources (rte_eth_dev_release_port()) so PMD specific '.dev_close()' should: - stop forwarding - clean PMD private resources If agreed on above, the task is: - '.dev_close()' - stop forwarding - clean PMD private resources - '.remove()' - call '.dev_close()' A question is if application should call 'rte_eth_dev_stop()' explicitly before close or should it be part of close? For (2) it makes sense app call the stop explicitly, but for device remove it is not clear who to stop the forwarding, for this case 'dev_close()' stopping forwarding makes things easier. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by dpdk.space (Postfix) with ESMTP id DA1BEA0679 for ; Mon, 29 Apr 2019 18:51:31 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 9D5051B10C; Mon, 29 Apr 2019 18:51:31 +0200 (CEST) Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by dpdk.org (Postfix) with ESMTP id DF4CF1B107 for ; Mon, 29 Apr 2019 18:51:29 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 29 Apr 2019 09:51:21 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,410,1549958400"; d="scan'208";a="165972201" Received: from fyigit-mobl.ger.corp.intel.com (HELO [10.237.221.33]) ([10.237.221.33]) by fmsmga002.fm.intel.com with ESMTP; 29 Apr 2019 09:51:10 -0700 To: Thomas Monjalon , "John W. Linville" , Xiaolong Ye , Qi Zhang , Shepard Siegel , Ed Czeck , John Miller , Igor Russkikh , Pavel Belous , Allain Legacy , Matt Peters , Ravi Kumar , Rasesh Mody , Shahed Shaikh , Ajit Khaparde , Somnath Kotur , Chas Williams , Rahul Lakkireddy , Hemant Agrawal , Shreyansh Jain , Wenzhuo Lu , Marcin Wojtas , Michal Krawczyk , Guy Tzalik , Evgeny Schemeilin , Gagandeep Singh , Pankaj Chauhan , John Daley , Hyong Youb Kim , Gaetan Rivet , Xiao Wang , Beilei Xing , Jingjing Wu , Qiming Yang , Konstantin Ananyev , Shijith Thotton , Srisivasubramanian Srinivasan , Matan Azrad , Shahaf Shuler , Yongseok Koh , Zyta Szpak , Liron Himi , Alan Winkowski , Tomasz Duszynski , Stephen Hemminger , "K. Y. Srinivasan" , Haiyang Zhang , Rastislav Cernay , Jan Remes , Alejandro Lucero , Tetsuya Mukawa , Jerin Jacob , Bruce Richardson , Andrew Rybchenko , Jasvinder Singh , Cristian Dumitrescu , Keith Wiles , Maciej Czekaj , Maxime Coquelin , Tiwei Bie , Zhihong Wang , Yong Wang , Anatoly Burakov Cc: dev@dpdk.org References: <30528485.5cHeq7CNxZ@xps> From: Ferruh Yigit Openpgp: preference=signencrypt Autocrypt: addr=ferruh.yigit@intel.com; prefer-encrypt=mutual; keydata= mQINBFXZCFABEADCujshBOAaqPZpwShdkzkyGpJ15lmxiSr3jVMqOtQS/sB3FYLT0/d3+bvy qbL9YnlbPyRvZfnP3pXiKwkRoR1RJwEo2BOf6hxdzTmLRtGtwWzI9MwrUPj6n/ldiD58VAGQ +iR1I/z9UBUN/ZMksElA2D7Jgg7vZ78iKwNnd+vLBD6I61kVrZ45Vjo3r+pPOByUBXOUlxp9 GWEKKIrJ4eogqkVNSixN16VYK7xR+5OUkBYUO+sE6etSxCr7BahMPKxH+XPlZZjKrxciaWQb +dElz3Ab4Opl+ZT/bK2huX+W+NJBEBVzjTkhjSTjcyRdxvS1gwWRuXqAml/sh+KQjPV1PPHF YK5LcqLkle+OKTCa82OvUb7cr+ALxATIZXQkgmn+zFT8UzSS3aiBBohg3BtbTIWy51jNlYdy ezUZ4UxKSsFuUTPt+JjHQBvF7WKbmNGS3fCid5Iag4tWOfZoqiCNzxApkVugltxoc6rG2TyX CmI2rP0mQ0GOsGXA3+3c1MCdQFzdIn/5tLBZyKy4F54UFo35eOX8/g7OaE+xrgY/4bZjpxC1 1pd66AAtKb3aNXpHvIfkVV6NYloo52H+FUE5ZDPNCGD0/btFGPWmWRmkPybzColTy7fmPaGz cBcEEqHK4T0aY4UJmE7Ylvg255Kz7s6wGZe6IR3N0cKNv++O7QARAQABtCVGZXJydWggWWln aXQgPGZlcnJ1aC55aWdpdEBpbnRlbC5jb20+iQJVBBMBAgA/AhsDBgsJCAcDAgYVCAIJCgsE FgIDAQIeAQIXgBYhBNI2U4dCLsKE45mBx/kz60PfE2EfBQJbughWBQkHwjOGAAoJEPkz60Pf E2Eft84QAIbKWqhgqRfoiw/BbXbA1+qm2o4UgkCRQ0yJgt9QsnbpOmPKydHH0ixCliNz1J8e mRXCkMini1bTpnzp7spOjQGLeAFkNFz6BMq8YF2mVWbGEDE9WgnAxZdi0eLY7ZQnHbE6AxKL SXmpe9INb6z3ztseFt7mqje/W/6DWYIMnH3Yz9KzxujFWDcq8UCAvPkxVQXLTMpauhFgYeEx Nub5HbvhxTfUkapLwRQsSd/HbywzqZ3s/bbYMjj5JO3tgMiM9g9HOjv1G2f1dQjHi5YQiTZl 1eIIqQ3pTic6ROaiZqNmQFXPsoOOFfXF8nN2zg8kl/sSdoXWHhama5hbwwtl1vdaygQYlmdK H2ueiFh/UvT3WG3waNv2eZiEbHV8Rk52Xyn2w1G90lV0fYC6Ket1Xjoch7kjwbx793Kz/RfQ rmBY8/S4DTGn3oq3dMdQY+b6+7VMUeLMMh2CXYO9ErkOq+qNTD1IY+cBAkXnaDbQfz0zbste ZGWH74FAZ9nCpDOqbRTrBL42aMGhfOWEyeA1x7+hl6JZfabBWAuf4nnCXuorKHzBXTrf7u7p fXsKQClWRW77PF1VmzrtKNVSytQAmlCWApQIw20AarFipXmVdIjHmJPU611WoyxZPb4JTOxx 5cv9B+nr/RIB+v5dcStyHCCwO1be7nBDdCgd4F6kTQPLuQINBFfWTL4BEACnNA29e8TarUsB L5n6eLZHXcFvVwNLVlirWOClHXf44o2KnN3ww+eBEmKVfEFo9MSuGDNHS8Zw1NiGMYxLIUgd U6gGrVVs/VrQWL82pbMk6jCj98N+BXIri+6K1z+AImz7ax7iF1kDgRAnFWU0znWWBgM2mM8Y gDjcxfXk4sCKnvf6Gjo08Ey5zmqx7dekAKU2EEp8Q1EJY3jbymLdZWRP4AFFMTS1rGMk0/tt v71NBg1GobCcbNfn9chK/jhqxYhAJqq86RdJQkt3/9x1U1Oq0vXCt4JVVHmkxePtUiuWTTt+ aYlUAsKYZsWvncExvw77x2ArYDmaK0yfjh37wp0lY7DOJHFxoyT8tyWZlLci/VMRG2Ja33xj 0CN4C1yBg+QDeV3QFxQo42iA/ykdXPUR3ezmsND3XKvVLTC4DNb3V/EZQ7jBj64+bEK0VW4G B31VP00ApNQvSoczsIOAKdk97RNbpmPw6q10ILIB+9T1xbnFYzshzGF17oC0/GENIHATx8vZ masOZoDiOZQpeneLgnFE9JfzhLTxv6wNZcc/HLXRQVTkDsQr8ERtkAoHCf1E5+b5Yr7pfnE4 YuhET746o25S53ELUYPIs49qoJsEJL34/oexMfPGyPIlrbufiNyty5jc/1MRwUlhJlJ5IOHy ZUa+6CLR7GdImusFkPJUJwARAQABiQI8BBgBAgAmAhsMFiEE0jZTh0IuwoTjmYHH+TPrQ98T YR8FAlu6CHAFCQXE7zIACgkQ+TPrQ98TYR9nXxAAqNBgkYNyGuWUuy0GwDQCbu3iiMyH1+D7 llafPcK4NYy1Z4AYuVwC9nmLaoj+ozdqS3ncRo57ncRsKEJC46nDJJZYZ5LSJVn63Y3NBF86 lxQAgjj2oyZEwaLKtKbAFsXL43jv1pUGgSvWwYtDwHITXXFQto9rZEuUDRFSx4sg9OR+Q6/6 LY+nQQ3OdHlBkflzYMPcWgDcvcTAO6yasLEUf7UcYoSWTyMYjLB4QuNlXzTswzGVMssJF/vo V8lD1eqqaSUWG3STF6GVLQOr1NLvN5+kUBiEStHFxBpgSCvYY9sNV8FS6N24CAWMBl+10W+D 2h1yiiP5dOdPcBDYKsgqDD91/sP0WdyMJkwdQJtD49f9f+lYloxHnSAxMleOpyscg1pldw+i mPaUY1bmIknLhhkqfMmjywQOXpac5LRMibAAYkcB8v7y3kwELnt8mhqqZy6LUsqcWygNbH/W K3GGt5tRpeIXeJ25x8gg5EBQ0Jnvp/IbBYQfPLtXH0Myq2QuAhk/1q2yEIbVjS+7iowEZNyE 56K63WBJxsJPB2mvmLgn98GqB4G6GufP1ndS0XDti/2K0o8rep9xoY/JDGi0n0L0tk9BHyoP Y7kaEpu7UyY3nVdRLe5H1/MnFG8hdJ97WqnPS0buYZlrbTV0nRFL/NI2VABl18vEEXvNQiO+ vM8= Message-ID: Date: Mon, 29 Apr 2019 17:51:09 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <30528485.5cHeq7CNxZ@xps> Content-Type: text/plain; charset="UTF-8" Content-Language: en-US Content-Transfer-Encoding: 8bit Subject: Re: [dpdk-dev] CALL to eth PMD maintainers: complete closing of port X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Message-ID: <20190429165109._9oMrST6lABUgfB3kQrsOu3MZHrq5g28P32R69NVQ9k@z> On 4/18/2019 11:59 AM, Thomas Monjalon wrote: > Hi all, > > Since DPDK 18.11, the behaviour of the close operation is changed > if RTE_ETH_DEV_CLOSE_REMOVE is enabled in the driver: > port is released (i.e. totally freed and data erased) on close. > This new behaviour is enabled per driver for a migration period. > > Looking at the code, you can see these comments: > /* old behaviour: only free queue arrays */ > RTE_ETHDEV_LOG(DEBUG, "Port closing is using an old behaviour.\n" > "The driver %s should migrate to the new behaviour.\n", > /* new behaviour: send event + reset state + free all data */ > > You can find an advice in the commit: > http://git.dpdk.org/dpdk/commit/?id=23ea57a2a > " > When enabling RTE_ETH_DEV_CLOSE_REMOVE, > the PMD must free all its private resources for the port, > in its dev_close function. > It is advised to call the dev_close function in the remove function > in order to support removing a device without closing its ports. > " > > It would be great to complete this migration for the next LTS > version, which will be 19.11. > It means the work should be ideally finished during the summer. I would like to detail a little more what needs to be done, mainly for the sake of the discussion, please comment if something missing/wrong. There are two exit paths for driver: 1) Hotplug remove the device rte_dev_remove() OR rte_eal_hotplug_remove() 2) Application exit: rte_eth_dev_close() (1) can be called without ethdev stop and close functions called, so the path should cover those functions. And in the PMD entry point in this path is .remove() function. In this .remove() function PMD should: - stop forwarding - clean PMD private resources (dev_close() ? ) - clean ethdev generic resources (rte_eth_dev_release_port() ? ) - remove device resources, which already done by remove APIs (2) ethdev won't be usable after "rte_eth_dev_close()" and it should clear PMD private and ethdev generic resources. With RTE_ETH_DEV_CLOSE_REMOVE flag 'rte_eth_dev_close()' will free generic ethdev resources (rte_eth_dev_release_port()) so PMD specific '.dev_close()' should: - stop forwarding - clean PMD private resources If agreed on above, the task is: - '.dev_close()' - stop forwarding - clean PMD private resources - '.remove()' - call '.dev_close()' A question is if application should call 'rte_eth_dev_stop()' explicitly before close or should it be part of close? For (2) it makes sense app call the stop explicitly, but for device remove it is not clear who to stop the forwarding, for this case 'dev_close()' stopping forwarding makes things easier.