On 31 May 2023, at 11:29, Maxime Coquelin wrote:
> On 5/31/23 08:19, Xia, Chenbo wrote:
>>> -----Original Message-----
>>> From: Maxime Coquelin <maxime.coque...@redhat.com>
>>> Sent: Tuesday, May 30, 2023 11:17 PM
>>> To: Thomas Monjalon <tho...@monjalon.net>; Eelco Chaudron
>>> <echau...@redhat.com>; Xia, Chenbo <chenbo....@intel.com>;
>>> david.march...@redhat.com
>>> Cc: dev@dpdk.org
>>> Subject: Re: [PATCH v3 4/4] vhost: add device op to offload the interrupt
>>> kick
>>>
>>>
>>>
>>> On 5/30/23 15:16, Thomas Monjalon wrote:
>>>> 30/05/2023 15:02, Maxime Coquelin:
>>>>>
>>>>> On 5/17/23 11:09, Eelco Chaudron wrote:
>>>>>> This patch adds an operation callback which gets called every time the
>>>>>> library wants to call eventfd_write(). This eventfd_write() call could
>>>>>> result in a system call, which could potentially block the PMD thread.
>>>>>>
>>>>>> The callback function can decide whether it's ok to handle the
>>>>>> eventfd_write() now or have the newly introduced function,
>>>>>> rte_vhost_notify_guest(), called at a later time.
>>>>>>
>>>>>> This can be used by 3rd party applications, like OVS, to avoid system
>>>>>> calls being called as part of the PMD threads.
>>>>>>
>>>>>> Signed-off-by: Eelco Chaudron <echau...@redhat.com>
>>>>>> ---
>>>>>> lib/vhost/meson.build | 2 ++
>>>>>> lib/vhost/rte_vhost.h | 23 +++++++++++++++++-
>>>>>> lib/vhost/socket.c | 63
>>> ++++++++++++++++++++++++++++++++++++++++++++++---
>>>>>> lib/vhost/version.map | 9 +++++++
>>>>>> lib/vhost/vhost.c | 38 ++++++++++++++++++++++++++++++
>>>>>> lib/vhost/vhost.h | 58 ++++++++++++++++++++++++++++++++------
>>> -------
>>>>>> 6 files changed, 171 insertions(+), 22 deletions(-)
>>>>>>
>>>>>
>>>>>
>>>>> The patch looks good to me, but that's the first time we use function
>>>>> versioning in Vhost library, so I'd like another pair of eyes to be
>>> sure
>>>>> I don't miss anything.
>>>>>
>>>>> Reviewed-by: Maxime Coquelin <maxime.coque...@redhat.com>
>>>>>
>>>>> Thomas, do we need to mention it somewhere in the release note?
>>>>
>>>> If compatibility is kept, I think we don't need to mention it.
>>>>
>>>>
>>>
>>> Thanks Thomas for the information.
>>>
>>> Maxime
>>
>> About release note, except the versioning, there is also one new API
>> introduced
>> in this patch, so we still need to mention this in release note
>
> Right, good catch.
> Eelco, let me know what you would put, I'll add it while applying (No
> need for a new revision).
Thanks guys! What about the following release note addition:
* **Added callback API support for interrupt handling in the vhost library.**
A new callback, guest_notify, is introduced that can be used to handle the
interrupt kick outside of the datapath fast path. In addition, a new API,
rte_vhost_notify_guest(), is added to raise the interrupt outside of the past
path.
Please change if you see fit.
Thanks,
Eelco
> Thanks,
> Maxime
>
>> Thanks,
>> Chenbo
