From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <ferruh.yigit@intel.com>
Received: from mga02.intel.com (mga02.intel.com [134.134.136.20])
 by dpdk.org (Postfix) with ESMTP id 4FB90A48F
 for <dev@dpdk.org>; Tue, 17 Apr 2018 13:26:49 +0200 (CEST)
X-Amp-Result: SKIPPED(no attachment in message)
X-Amp-File-Uploaded: False
Received: from fmsmga006.fm.intel.com ([10.253.24.20])
 by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384;
 17 Apr 2018 04:26:48 -0700
X-ExtLoop1: 1
X-IronPort-AV: E=Sophos;i="5.48,463,1517904000"; d="scan'208";a="221080281"
Received: from fyigit-mobl.ger.corp.intel.com (HELO [10.237.221.42])
 ([10.237.221.42])
 by fmsmga006.fm.intel.com with ESMTP; 17 Apr 2018 04:26:43 -0700
To: Tiwei Bie <tiwei.bie@intel.com>
Cc: Qi Zhang <qi.z.zhang@intel.com>, Xiao Wang <xiao.w.wang@intel.com>,
 John McNamara <john.mcnamara@intel.com>,
 Marko Kovacevic <marko.kovacevic@intel.com>,
 Beilei Xing <beilei.xing@intel.com>, Wenzhuo Lu <wenzhuo.lu@intel.com>,
 Rasesh Mody <rasesh.mody@cavium.com>, Harish Patil
 <harish.patil@cavium.com>, Shahed Shaikh <shahed.shaikh@cavium.com>,
 Tetsuya Mukawa <mtetsuyah@gmail.com>, Yuanhan Liu <yliu@fridaylinux.org>,
 Maxime Coquelin <maxime.coquelin@redhat.com>, Marcin Wojtas
 <mw@semihalf.com>, Michal Krawczyk <mk@semihalf.com>,
 Guy Tzalik <gtzalik@amazon.com>, Evgeny Schemeilin <evgenys@amazon.com>,
 Konstantin Ananyev <konstantin.ananyev@intel.com>,
 Adrien Mazarguil <adrien.mazarguil@6wind.com>,
 Nelio Laranjeiro <nelio.laranjeiro@6wind.com>,
 Yongseok Koh <yskoh@mellanox.com>, dev@dpdk.org
References: <20180313180534.232296-1-ferruh.yigit@intel.com>
 <20180410154102.uv7og3ff4y5ylc3m@debian>
 <bf29cef8-7340-d8d5-6508-e4ed8625a177@intel.com>
 <20180414105546.25vqtpcfkexwlkhp@debian>
 <ed96bc80-d8c9-d276-1149-c7a1d7d829cb@intel.com>
 <20180417045427.6guh7x7yqpyfdnwj@debian>
From: Ferruh Yigit <ferruh.yigit@intel.com>
Openpgp: preference=signencrypt
Autocrypt: addr=ferruh.yigit@intel.com; prefer-encrypt=mutual; keydata=
 xsFNBFXZCFABEADCujshBOAaqPZpwShdkzkyGpJ15lmxiSr3jVMqOtQS/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++O7QARAQABzSVGZXJydWggWWln
 aXQgPGZlcnJ1aC55aWdpdEBpbnRlbC5jb20+wsF+BBMBAgAoAhsDBgsJCAcDAgYVCAIJCgsE
 FgIDAQIeAQIXgAUCWZR3VQUJB33WBQAKCRD5M+tD3xNhH6DWEACVhEb8q1epPwZrUDoxzu7E
 TS1b8tmabOmnjXZRs6+EXgUVHkp2xxkCfDmL3pa5bC0G/74aJnWjNsdvE05V1cb4YK4kRQ62
 FwDQ+hlrFrwFB3PtDZk1tpkzCRHvJgnIil+0MuEh32Y57ig6hy8yO8ql7Lohyrnpfk/nNpm4
 jQGEF5qEeHcEFe1AZQlPHN/STno8NZSz2nl0b2cw+cujN1krmvB52Ah/2KugQ6pprVyrGrzB
 c34ZQO9OsmSjJlETCZk6EZzuhfe16iqBFbOSadi9sPcJRwaUQBid+xdFWl7GQ8qC3zNPibSF
 HmU43yBZUqJDZlhIcl6/cFpOSjv2sDWdtjEXTDn5y/0FsuY0mFE78ItC4kCTIVk17VZoywcd
 fmbbnwOSWzDq7hiUYuQGkIudJw5k/A1CMsyLkoUEGN3sLfsw6KASgS4XrrmPO4UVr3mH5bP1
 yC7i1OVNpzvOxtahmzm481ID8sk72GC2RktTOHb0cX+qdoiMMfYgo3wRRDYCBt6YoGYUxF1p
 msjocXyqToKhhnFbXLaZlVfnQ9i2i8jsj9SKig+ewC2p3lkPj6ncye9q95bzhmUeJO6sFhJg
 Hiz6syOMg8yCcq60j07airybAuHIDNFWk0gaWAmtHZxLObZx2PVn2nv9kLYGohFekw0AOsIW
 ta++5m48dnCoAc7BTQRX1ky+ARAApzQNvXvE2q1LAS+Z+ni2R13Bb1cDS1ZYq1jgpR13+OKN
 ipzd8MPngRJilXxBaPTErhgzR0vGcNTYhjGMSyFIHVOoBq1VbP1a0Fi/NqWzJOowo/fDfgVy
 K4vuitc/gCJs+2se4hdZA4EQJxVlNM51lgYDNpjPGIA43MX15OLAip73+ho6NPBMuc5qse3X
 pAClNhBKfENRCWN428pi3WVkT+ABRTE0taxjJNP7bb+9TQYNRqGwnGzX5/XISv44asWIQCaq
 vOkXSUJLd//cdVNTqtL1wreCVVR5pMXj7VIrlk07fmmJVALCmGbFr53BMb8O+8dgK2A5mitM
 n44d+8KdJWOwziRxcaMk/LclmZS3Iv1TERtiWt98Y9AjeAtcgYPkA3ld0BcUKONogP8pHVz1
 Ed3s5rDQ91yr1S0wuAzW91fxGUO4wY+uPmxCtFVuBgd9VT9NAKTUL0qHM7CDgCnZPe0TW6Zj
 8OqtdCCyAfvU9cW5xWM7Icxhde6AtPxhDSBwE8fL2ZmrDmaA4jmUKXp3i4JxRPSX84S08b+s
 DWXHPxy10UFU5A7EK/BEbZAKBwn9ROfm+WK+6X5xOGLoRE++OqNuUudxC1GDyLOPaqCbBCS9
 +P6HsTHzxsjyJa27n4jcrcuY3P9TEcFJYSZSeSDh8mVGvugi0exnSJrrBZDyVCcAEQEAAcLB
 ZQQYAQIADwIbDAUCWZR1ZwUJA59cIQAKCRD5M+tD3xNhH5b+D/9XG44Ci6STdcA5RO/ur05J
 EE3Ux1DCHZ5V7vNAtX/8Wg4l4GZfweauXwuJ1w7Sp7fklwcNC6wsceI+EmNjGMqfIaukGetG
 +jBGqsQ7moOZodfXUoCK98gblKgt/BPYMVidzlGC8Q/+lZg1+o29sPnwImW+MXt/Z5az/Z17
 Qc265g+p5cqJHzq6bpQdnF7Fu6btKU/kv6wJghENvgMXBuyThqsyFReJWFh2wfaKyuix3Zyj
 ccq7/blkhzIKmtFWgDcgaSc2UAuJU+x9nuYjihW6WobpKP/nlUDu3BIsbIq09UEke+uE/QK+
 FJ8PTJkAsXOf1Bc2C0XbW4Y2hf103+YY6L8weUCBsWC5VH5VtVmeuh26ENURclwfeXhWQ9Og
 77yzpTXWr5g1Z0oLpYpWPv745J4bE7pv+dzxOrFdM1xNkzY2pvXph/A8OjxZNQklDkHQ7PIB
 Lki5L2F4XkEOddUUQchJwzMqTPsggPDmGjgLZrqgO+s4ECZK5+nLD3HEpAbPa3JLDaScy+90
 Nu1lAqPUHSnP3vYZVw85ZYm6UCxHE4VLMnnJsN09ZhsOSVR+GyP5Nyw9rT1V3lcsuH7M5Naa
 2Xobn9m7l9bRCD/Ji8kG15eV1WTxx1HXVQGjdUYDI7UwegBNbwMLh17XDy+3sn/6SgcqtECA
 Q6pZKA2mTQxEKMLBZQQYAQIADwIbDAUCWZR3hQUJA59eRwAKCRD5M+tD3xNhH4a/D/4jLAZu
 UhvU1swWcNEVVCELZ0D3LOV14XcY2MXa3QOpeZ9Bgq7YYJ4S5YXK+SBQS0FkRZdjGNvlGZoG
 ZdpU+NsQmQFhqHGwX0IT9MeTFM8uvKgxNKGwMVcV9g0IOqwBhGHne+BFboRA9362fgGW5AYQ
 zT0mzzRKEoOh4r3AQvbM6kLISxo0k1ujdYiI5nj/5WoKDqxTwwfuN1uDUHsWo3tzenRmpMyU
 NyW3Dc+1ajvXLyo09sRRq7BnM99Rix1EGL8Qhwy+j0YAv+FuspWxUX9FxXYho5PvGLHLsHfK
 FYQ7x/RRbpMjkJWVfIe/xVnfvn4kz+MTA5yhvsuNi678fLwY9hBP0y4lO8Ob2IhEPdfnTuIs
 tFVxXuelJ9xAe5TyqP0f+fQjf1ixsBZkqOohsBXDfje0iaUpYa/OQ/BBeej0dUdg2JEu4jAC
 x41HpVCnP9ipLpD0fYz1d/dX0F/VY2ovW6Eba/y/ngOSAR6C+u881m7oH2l0G47MTwkaQCBA
 bLGXPj4TCdX3lftqt4bcBPBJ+rFAnJmRHtUuyyaewBnZ81ZU2YAptqFM1kTh+aSvMvGhfVsQ
 qZL2rk2OPN1hg+KXhErlbTZ6oPtLCFhSHQmuxQ4oc4U147wBTUuOdwNjtnNatUhRCp8POc+3
 XphVR5G70mnca1E2vzC77z+XSlTyRA==
Message-ID: <bd760785-67c6-3ff2-027f-79fd51438902@intel.com>
Date: Tue, 17 Apr 2018 12:26:42 +0100
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101
 Thunderbird/52.7.0
MIME-Version: 1.0
In-Reply-To: <20180417045427.6guh7x7yqpyfdnwj@debian>
Content-Type: text/plain; charset=utf-8
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Subject: Re: [dpdk-dev] [PATCH] drivers/net: update link status
X-BeenThere: dev@dpdk.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: DPDK patches and discussions <dev.dpdk.org>
List-Unsubscribe: <https://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: <https://dpdk.org/ml/listinfo/dev>,
 <mailto:dev-request@dpdk.org?subject=subscribe>
X-List-Received-Date: Tue, 17 Apr 2018 11:26:49 -0000

On 4/17/2018 5:54 AM, Tiwei Bie wrote:
> On Mon, Apr 16, 2018 at 05:10:24PM +0100, Ferruh Yigit wrote:
>> On 4/14/2018 11:55 AM, Tiwei Bie wrote:
>>> On Fri, Apr 13, 2018 at 10:53:55PM +0100, Ferruh Yigit wrote:
>>>> On 4/10/2018 4:41 PM, Tiwei Bie wrote:
>>>>> On Tue, Mar 13, 2018 at 06:05:34PM +0000, Ferruh Yigit wrote:
>>>>>> Update link status related feature document items and minor updates in
>>>>>> some link status related functions.
>>>>>>
>>>>>> Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
>>>>>> ---
>>>>>>  doc/guides/nics/features/fm10k.ini      | 2 ++
>>>>>>  doc/guides/nics/features/fm10k_vf.ini   | 2 ++
>>>>>>  doc/guides/nics/features/i40e_vf.ini    | 1 +
>>>>>>  doc/guides/nics/features/igb_vf.ini     | 1 +
>>>>>>  doc/guides/nics/features/qede.ini       | 1 -
>>>>>>  doc/guides/nics/features/qede_vf.ini    | 1 -
>>>>>>  doc/guides/nics/features/vhost.ini      | 2 --
>>>>>>  doc/guides/nics/features/virtio_vec.ini | 1 +
>>>>>>  drivers/net/e1000/em_ethdev.c           | 2 +-
>>>>>>  drivers/net/ena/ena_ethdev.c            | 2 +-
>>>>>>  drivers/net/fm10k/fm10k_ethdev.c        | 6 ++----
>>>>>>  drivers/net/i40e/i40e_ethdev_vf.c       | 2 +-
>>>>>>  drivers/net/ixgbe/ixgbe_ethdev.c        | 2 +-
>>>>>>  drivers/net/mlx4/mlx4_ethdev.c          | 2 +-
>>>>>>  drivers/net/mlx5/mlx5_ethdev.c          | 2 +-
>>>>>>  15 files changed, 15 insertions(+), 14 deletions(-)
>>>>> [...]
>>>>>> diff --git a/doc/guides/nics/features/vhost.ini b/doc/guides/nics/features/vhost.ini
>>>>>> index dffd1f493..31302745a 100644
>>>>>> --- a/doc/guides/nics/features/vhost.ini
>>>>>> +++ b/doc/guides/nics/features/vhost.ini
>>>>>> @@ -4,8 +4,6 @@
>>>>>>  ; Refer to default.ini for the full list of available PMD features.
>>>>>>  ;
>>>>>>  [Features]
>>>>>> -Link status          = Y
>>>>>> -Link status event    = Y
>>>>>
>>>>> I think vhost PMD supports above features.
>>>>
>>>> I am not able to find where it is supported.
>>>>
>>>> Some virtual PMDs report fixed link, with empty link_update() dev_ops, and they
>>>> are not reported as supporting Link status, as far as I can see vhost also one
>>>> of them.
>>>>
>>>> And for Link status event, PMD needs to support LSC interrupts and should
>>>> register interrupt handler for it, which I can't find for vhost.
>>>>
>>>> I will send next version without updating above one, please point me where these
>>>> support added if I missed them.
>>>
>>> In drivers/net/vhost/rte_eth_vhost.c you could find below functions:
>>>
>>> static int
>>> new_device(int vid)
>>> {
>>> 	......
>>>
>>> 	eth_dev->data->dev_link.link_status = ETH_LINK_UP;
>>>
>>> 	......
>>>
>>> 	_rte_eth_dev_callback_process(eth_dev, RTE_ETH_EVENT_INTR_LSC, NULL);
>>>
>>> 	......
>>> }
>>>
>>> static void
>>> destroy_device(int vid)
>>> {
>>> 	......
>>>
>>> 	eth_dev->data->dev_link.link_status = ETH_LINK_DOWN;
>>>
>>> 	......
>>>
>>> 	_rte_eth_dev_callback_process(eth_dev, RTE_ETH_EVENT_INTR_LSC, NULL);
>>>
>>> 	......
>>> }
>>>
>>> They are the callbacks for vhost library.
>>>
>>> When a frontend (e.g. QEMU) is connected to this vhost backend
>>> and the frontend virtio device becomes ready, new_device() will
>>> be called by the vhost library, and the link status will be
>>> updated to UP.
>>>
>>> And when e.g. the connection is closed, destroy_device() will be
>>> called by the vhost library, and the link status will be updated
>>> to DOWN.
>>
>>
>> Got it. This behavior is similar for virtual PMDs. Provide static link
>> information and update link as UP during start and update it as DOWN during stop.
> 
> No, the link status isn't updated during vhost PMD start
> and stop. When the vhost PMD has been started, the link
> status still may be DOWN. The link status becomes UP only
> when the QEMU (it's another virtual machine process which
> has a virtio device) connects to this vhost PMD via a UNIX
> socket and the virtio driver in the virtual machine has
> setup the virtio device of the virtual machine.
> 
> So if vhost PMD reports the link status as DOWN, it means
> there is no QEMU (virtual machine) connects to it or the
> virtio device in the virtual machine hasn't been setup.
> (PS. The frontend can also be virtio-user PMD besides QEMU)

I believe announcing link feature reporting on virtual pmds still in gray area,
but because of qemu involvement in vhost case, I will keep link feature but will
drop link event.

Will send a new patch to reflect this.

Thanks,
ferruh

> 
> Thanks
> 
>>
>> Other virtual PMDs doesn't report this feature, so removed from vhost as well
>> for consistency.
>>
>>>
>>> So vhost PMD reports meaningful link status and also generates
>>> link status events.
>>
>> Yes PMD process user callbacks on link change [1], but I am not sure that is
>> what meant from "link status event", what I understand is link interrupts
>> supported in PMD level which seems not the case for vhost.
>>
>> [1]
>> This is something else but why calling user callback in link update is in PMD
>> discretion, shouldn't it be something done automatically in ethdev layer, somehow.
>>
>>>
>>> Thanks
>>>
>>