[dpdk-dev] [PATCH v3 0/3] enhance TX checksum command and csum forwarding engine

[Ananyev, Konstantin]

Hi Frank,

> -----Original Message-----
> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Liu, Jijiang
> Sent: Wednesday, January 07, 2015 2:04 AM
> To: 'Olivier MATZ'
> Cc: dev at dpdk.org
> Subject: Re: [dpdk-dev] [PATCH v3 0/3] enhance TX checksum command and csum forwarding engine
> 
> Hi Olivier,
> 
> > -----Original Message-----
> > From: Olivier MATZ [mailto:olivier.matz at 6wind.com]
> > Sent: Saturday, December 13, 2014 12:33 AM
> > To: Liu, Jijiang
> > Cc: dev at dpdk.org
> > Subject: Re: [dpdk-dev] [PATCH v3 0/3] enhance TX checksum command and
> > csum forwarding engine
> >
> > Hello,
> >
> > On 12/12/2014 04:48 AM, Liu, Jijiang wrote:
> > > The 'hw/sw' option  is used to set/clear the flag of enabling TX tunneling packet
> > checksum hardware offload in testpmd application.
> >
> > This is not clear at all.
> > In your command, there is (hw|sw|none).
> > Are you talking about inner or outer?
> > Is this command useful for any kind of packet?
> > How does it combine with "tx_checksum set outer-ip (hw|sw)"?
> >
> 
> I rethink these TX checksum commands in this patch set and agree with you that we should make some changes for having clear
> meaning for them.
> 
> There are  3 commands in patch set as follows,
> 1. tx_checksum set tunnel (hw|sw|none) (port-id)
> 
> Now I also think the command 1 may confuse user, they probably don't understand  why we need 'hw' or 'sw' option and when  to
> use the two option,
> so I will replace the command with 'tx_checksum set hw-tunnel-mode (on|off) (port-id)' command.

I am a bit confused here, could you explain what would be a behaviour for 'on' and 'off'?
Konstantin

> 
> 2. tx_checksum set outer-ip (hw|sw) (port-id)
> 3. tx_checksum set  (ip|udp|tcp|sctp) (hw|sw) (port-id)
> 
> The command 2 will be merged into command 3, the new command is ' tx_checksum set  (outer-ip|ip|udp|tcp|sctp) (hw|sw) (port-
> id)'.
> 
> These most of the cases in http://dpdk.org/ml/archives/dev/2014-December/009213.html will be covered by using the two
> commands
> 
> The command 'tx_checksum set hw-tunnel-mode (on|off)  (port-id)' is used to set/clear  TESTPMD_TX_OFFLOAD_TUNNEL_CKSUM
> flag.
> Actually, the PKT_TX_UDP_TUNNEL_PKT offload flag will be set if the testpmd flag is set, which tell driver/HW treat  that transmit
> packet as a tunneling packet.
> 
> When 'on' is set, which is able to meet Method B.1 and method C.
> 
> When 'off' is set, the TESTPMD_TX_OFFLOAD_TUNNEL_CKSUM is not needed to set, so the PKT_TX_UDP_TUNNEL_PKT offload flag is
> not needed to set,  then HW treat  that transmit packet as a non-tunneling packet. It is able to meet Method B.2.
> 
> As to case A, I think it is not mandatory to cover it in csum fwd engine for tunneling packet.
> 
> Is the above description clear for you?
> 
> > Regards,
> > Olivier