[dpdk-dev] [PATCH v2 0/3] vhost: disable iommu support by default

[Kevin Traynor]

On 11/07/2017 11:30 AM, Maxime Coquelin wrote:
> 
> 
> On 11/07/2017 12:25 PM, Kevin Traynor wrote:
>> On 11/07/2017 10:56 AM, Kavanagh, Mark B wrote:
>>>> From: Maxime Coquelin [mailto:maxime.coquelin at redhat.com]
>>>> Sent: Monday, November 6, 2017 8:38 PM
>>>> To: dev at dpdk.org; yliu at fridaylinux.org; Kavanagh, Mark B
>>>> <mark.b.kavanagh at intel.com>; thomas at monjalon.net; ktraynor at redhat.com
>>>> Cc: Maxime Coquelin <maxime.coquelin at redhat.com>
>>>> Subject: [PATCH v2 0/3] vhost: disable iommu support by default
>>>>
>>>> This series disables IOMMU feature by default, and introduce
>>>> a new flag passed at vhost device registration time to enable
>>>> it explicitly.
>>>>
>>>> When disabled, patch 1 also disables reply-ack protocol feature
>>>> to avoid Qemu v2.7.0-v2.9.0 reply-ack bug with multiqueue.
>>>>
>>>> Last patch adds a Vhost PMD "iommu-support" parameter to enable
>>>> the IOMMU feature.
>>>
> 
> Hi Kevin,
> 
>> Hi Maxime - OVS-DPDK does not use the vhost pmd, so that means that
>> iommu could not be used with OVS-DPDK at present. Did I get that right?
> 
> No :)
> 

Good :)

> This is supported both with and without using Vhost PMD.
> 
> When using the Vhost lib directly, you just have to pass
> RTE_VHOST_USER_IOMMU_SUPPORT flag to rte_vhost_driver_register(),
> this is patch 1.
> 
> When using Vhost PMD, passing the iommu-support=1 option to the vdev
> cmdline will set this flag, this is patch 2.
> 

Ah ok, just catching up, thanks for the ABC. It seems like a good
compromise, sorry for the noise.

> Thanks,
> Maxime
> 
>> Ciara proposed patches for vhost pmd in OVS-DPDK but it is quite an
>> intrusive change and has been postponed multiple times due to various
>> issues.
>>
>> thanks,
>> Kevin.
>>
>>> Hi Maxime,
>>>
>>> I'm happy to confirm that this patchset resolves the vhost user
>>> mutltiq issue for OvS-DPDK, with QEMU v2.7.1.
>>>
>>> Additionally, all of the individual patches look good - thanks for
>>> all of your efforts on this!
>>>
>>> Tested-by: Mark Kavanagh <mark.b.kavanagh at intel.com>
>>> Acked-by: Mark Kavanagh <mark.b.kavanagh at intel.com>
>>>
>>> Cheers,
>>> Mark
>>>
>>>>
>>>> Maxime Coquelin (3):
>>>>   vhost: disable reply-ack protocol feature if iommu feature disabled
>>>>   vhost: add flag to enable iommu support
>>>>   net: vhost: add iommu-support parameter to enable IOMMU feature
>>>>
>>>> doc/guides/nics/vhost.rst              |  5 +++++
>>>> doc/guides/prog_guide/vhost_lib.rst    | 14 ++++++++++++++
>>>> doc/guides/rel_notes/release_17_11.rst |  3 ++-
>>>> drivers/net/vhost/rte_eth_vhost.c      | 13 +++++++++++++
>>>> lib/librte_vhost/rte_vhost.h           |  1 +
>>>> lib/librte_vhost/socket.c              |  6 ++++++
>>>> lib/librte_vhost/vhost_user.c          | 24 ++++++++++++++++++++++--
>>>> 7 files changed, 63 insertions(+), 3 deletions(-)
>>>>
>>>> -- 
>>>> 2.13.6
>>>
>>