Re: [PATCH v3 0/3] enhance TX checksum command and csum forwarding engine

[Olivier MATZ <olivier.matz-pdR9zngts4EAvxtiuMwx3w@public.gmane.org>]

Hi,

Thank you Jijiang for taking the time to get back on this.

On 01/08/2015 11:54 AM, Ananyev, Konstantin wrote:
>> And we are able to test all of cases in  http://dpdk.org/ml/archives/dev/2014-December/009213.html
>>
>> Test case A:
>>
>> tx_checksum set sw-tunnel-mode off
>> tx_checksum set hw-tunnel-mode off
>> tx_checksum set  ip   hw
>>
>> test case B.1:
>>
>> tx_checksum set sw-tunnel-mode on
>> tx_checksum set hw-tunnel-mode on
>> tx_checksum set  ip   hw
>> tx_checksum set  tcp   hw
>>
>> test case B.2:
>>
>> tx_checksum set sw-tunnel-mode on
>> tx_checksum set hw-tunnel-mode off
>> tx_checksum set  ip   hw
>>
>> test case C:
>>
>> tx_checksum set sw-tunnel-mode on
>> tx_checksum set hw-tunnel-mode on
>> tx_checksum set  outer-ip   hw
>> tx_checksum set  ip   hw
>> tx_checksum set  tcp   hw

There is something I don't understand. A forward engine takes any packet
in input and output. Packets can be of any kind (eth/arp, eth/ip/tcp,
eth/vlan/ip/udp/vxlan/eth/ip/tcp, ...)

Today, the behavior of csum forward engine is defined for any kind of
packet. See the description and the table in
http://dpdk.org/ml/archives/dev/2014-December/009886.html

All packets that are not "Ether[/vlan]/(IP|IP6)/(UDP|TCP|SCTP)" or
"Ether[/vlan]/(IP|IP6)/UDP/VxLAN/Ether[/vlan]/(IP|IP6)/UDP|TCP|SCTP"
are forwarded without beeing modified.

In my understanding, the use-case you are describing correspond to
specific packet types. So a configuration would work only for one
packet format only. Is it correct?

I think that the test-pmd command API should define a behavior for
the csum forward engine for any packet. What do you think?

Regards,
Olivier