[ovs-dev] [PATCH V2 1/1] dpif-netlink: Log eth type 0x1234 not offloadable

Ilya Maximets i.maximets at samsung.com
Tue Jul 30 10:30:27 UTC 2019


On 30.07.2019 13:23, Eli Britstein wrote:
> 
> On 7/30/2019 1:10 PM, Ilya Maximets wrote:
>> On 03.07.2019 7:58, Eli Britstein wrote:
>>> Ethernet type 0x1234 is used for testing and not being offloadable. For
>>> testing offloadable features, log about using this value.
>>>
>>> Signed-off-by: Eli Britstein <elibr at mellanox.com>
>>> Acked-by: Roi Dayan <roid at mellanox.com>
>>> Signed-off-by: Eli Britstein <elibr at mellanox.com>
>>> Acked-by: Ben Pfaff <blp at ovn.org>
>>> ---
>>>   lib/dpif-netlink.c | 1 +
>>>   1 file changed, 1 insertion(+)
>>>
>>> diff --git a/lib/dpif-netlink.c b/lib/dpif-netlink.c
>>> index ba80a0079..a0d51ae61 100644
>>> --- a/lib/dpif-netlink.c
>>> +++ b/lib/dpif-netlink.c
>>> @@ -2007,6 +2007,7 @@ parse_flow_put(struct dpif_netlink *dpif, struct dpif_flow_put *put)
>>>   
>>>       /* When we try to install a dummy flow from a probed feature. */
>>>       if (match.flow.dl_type == htons(0x1234)) {
>>> +        VLOG_INFO_RL(&rl, "eth 0x1234 is special and not offloadable");
>>>           return EOPNOTSUPP;
>>>       }
>> But what is the purpose of this patch?  What is the use case?
> RH wanted to test that dl_type is offloaded. Coincidentally, they used 
> 0x1234, and it was not offloaded, and they didn't understand why, and 
> suggested a log message.

I'll take a closer look, but it seems that we just need to remove this
'if' statement and allow oflloading.

>>
>> Actually, it looks like we need to just remove above 'if' statement
>> entirely.  Just a few lines above there is a check if we are probing
>> or installing real flow:
>>
>>     if (put->flags & DPIF_FP_PROBE) {
>>         return EOPNOTSUPP;
>>     }
>>
>> So, we will never get there while probing.  But why we're restricting
>> this flow type from being offloaded?  'netdev_flow_put' will refuse
>> to offload if it doesn't know that flow type, but this shouldn't be
>> done here.
>>
>> In case we have a dummy flow without DPIF_FP_PROBE flag set, we need
>> to fix upper layers.  Is it the case?
> 
> I didn't look into it why we restrict it and if there is a real reason 
> why in this layer. You may be right, but I don't know.
> 
>>
>> Best regards, Ilya Maximets.


More information about the dev mailing list