Re: [dpdk-users] PTP client over DPDK

Re: [dpdk-users] PTP client over DPDK

[Marcin Kulawczuk]

Hi,

We are struggling with same problem as you (working on PTP implementation
in dpdk), so I've got a question to you, would you recommend solution 2 for
us or have you found some problems with it?

Thanks,
Marcin

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[dpdk-users] PTP client over DPDK

[Philippe CORNET]

Hi all,

I am currently wondering what is the best/cheapest way to implement a PTP client over DPDK:


1.       Implementing a custom PTP client over DPDK.
or

2.       Using LinuxPTP (http://linuxptp.sourceforge.net/) through KNI interface.

For solution 1, we can start from the PTP sample program, but it certainly requires quite some time to develop a smart and accurate client.

For solution 2, I have a proof-of-concept which works quite well, but it requires these modifications:

-          To build KNI with flag CONFIG_RTE_KNI_PREEMPT_DEFAULT=n to reduce latency of KNI

-          To patch kni_net.c to add a software timestamping of the skb (skb_tx_timestamp(skb)) in tx routine.

-          To patch LinuxPTP to avoid it checking the software-transmit time stamping capability of the KNI driver.

Solution 2 is tempting because it almost costs nothing in term of development time, but I am not sure that it is the good way to proceed...

Does anyone has strong arguments for or against this second solution?

Thanks,
Philippe