Re: [PATCH 3/6] net/vhost: enable compliant offloading mode

[Maxime Coquelin <maxime.coquelin@redhat.com>]

Hi Wenwu,

On 6/7/22 03:19, Ma, WenwuX wrote:
> Hi Maxime,
> 
>> -----Original Message-----
>> From: Xia, Chenbo <chenbo.xia@intel.com>
>> Sent: 2022年5月16日 21:40
>> To: Maxime Coquelin <maxime.coquelin@redhat.com>; dev@dpdk.org;
>> jasowang@redhat.com; david.marchand@redhat.com;
>> olivier.matz@6wind.com
>> Cc: stable@dpdk.org
>> Subject: RE: [PATCH 3/6] net/vhost: enable compliant offloading mode
>>
>>> -----Original Message-----
>>> From: Maxime Coquelin <maxime.coquelin@redhat.com>
>>> Sent: Monday, May 16, 2022 9:29 PM
>>> To: Xia, Chenbo <chenbo.xia@intel.com>; dev@dpdk.org;
>>> jasowang@redhat.com; david.marchand@redhat.com;
>> olivier.matz@6wind.com
>>> Cc: stable@dpdk.org
>>> Subject: Re: [PATCH 3/6] net/vhost: enable compliant offloading mode
>>>
>>> Hi Chenbo,
>>>
>>> On 5/16/22 15:26, Xia, Chenbo wrote:
>>>> Hi Maxime,
>>>>
>>>>> -----Original Message-----
>>>>> From: Maxime Coquelin <maxime.coquelin@redhat.com>
>>>>> Sent: Thursday, May 5, 2022 6:27 PM
>>>>> To: dev@dpdk.org; jasowang@redhat.com; Xia, Chenbo
>>> <chenbo.xia@intel.com>;
>>>>> david.marchand@redhat.com; olivier.matz@6wind.com
>>>>> Cc: stable@dpdk.org; Maxime Coquelin <maxime.coquelin@redhat.com>
>>>>> Subject: [PATCH 3/6] net/vhost: enable compliant offloading mode
>>>>>
>>>>> This patch enables the compliant offloading flags mode by default,
>>>>> which prevents the Rx path to set Tx offload flags, which is
>>>>> illegal. A new legacy-ol-flags devarg is introduced to enable the
>>>>> legacy behaviour.
>>>>>
>>>>> Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
>>>>> ---
>>>>>    doc/guides/nics/vhost.rst         |  6 ++++++
>>>>>    drivers/net/vhost/rte_eth_vhost.c | 19 ++++++++++++++++---
>>>>>    2 files changed, 22 insertions(+), 3 deletions(-)
>>>>>
>>>>> diff --git a/doc/guides/nics/vhost.rst b/doc/guides/nics/vhost.rst
>>>>> index ee802ec4a8..d7c0e2ade8 100644
>>>>> --- a/doc/guides/nics/vhost.rst
>>>>> +++ b/doc/guides/nics/vhost.rst
>>>>> @@ -64,6 +64,12 @@ The user can specify below arguments in `--vdev`
>>> option.
>>>>>        It is used to enable external buffer support in vhost library.
>>>>>        (Default: 0 (disabled))
>>>>>
>>>>> +#.  ``legacy-ol-flags``:
>>>>> +
>>>>> +    It is used to restore legacy behavior for offloading that was not
>>>>> +    compliant with offloading API.
>>>>> +    (Default: 0 (disabled))
>>>>> +
>>>>>    Vhost PMD event handling
>>>>>    ------------------------
>>>>>
>>>>> diff --git a/drivers/net/vhost/rte_eth_vhost.c
>>>>> b/drivers/net/vhost/rte_eth_vhost.c
>>>>> index 070f0e6dfd..0a2e8d9b29 100644
>>>>> --- a/drivers/net/vhost/rte_eth_vhost.c
>>>>> +++ b/drivers/net/vhost/rte_eth_vhost.c
>>>>> @@ -31,9 +31,10 @@ enum {VIRTIO_RXQ, VIRTIO_TXQ,
>> VIRTIO_QNUM};
>>>>>    #define ETH_VHOST_CLIENT_ARG		"client"
>>>>>    #define ETH_VHOST_IOMMU_SUPPORT		"iommu-support"
>>>>>    #define ETH_VHOST_POSTCOPY_SUPPORT	"postcopy-support"
>>>>> -#define ETH_VHOST_VIRTIO_NET_F_HOST_TSO "tso"
>>>>> -#define ETH_VHOST_LINEAR_BUF  "linear-buffer"
>>>>> -#define ETH_VHOST_EXT_BUF  "ext-buffer"
>>>>> +#define ETH_VHOST_VIRTIO_NET_F_HOST_TSO	"tso"
>>>>> +#define ETH_VHOST_LINEAR_BUF		"linear-buffer"
>>>>> +#define ETH_VHOST_EXT_BUF		"ext-buffer"
>>>>> +#define ETH_VHOST_LEGACY_OL_FLAGS	"legacy-ol-flags"
>>>>>    #define VHOST_MAX_PKT_BURST 32
>>>>>
> 
> ETH_VHOST_LEGACY_OL_FLAGS should be added into valid_arguments array.
> 
> static const char *valid_arguments[] = {
>          ETH_VHOST_IFACE_ARG,
>          ETH_VHOST_QUEUES_ARG,
>          ETH_VHOST_CLIENT_ARG,
>          ETH_VHOST_IOMMU_SUPPORT,
>          ETH_VHOST_POSTCOPY_SUPPORT,
>          ETH_VHOST_VIRTIO_NET_F_HOST_TSO,
>          ETH_VHOST_LINEAR_BUF,
>          ETH_VHOST_EXT_BUF,
>          NULL
> };

Thanks, good catch!
I missed to test this new devarg addition, fixing it for v2.

Maxime