Question about dpdk-pdump ring buffer

Question about dpdk-pdump ring buffer

[sakaia]

Question about dpdk-pdump ring buffer

With updating from 21.08 to 21.11, The packet capture is failed. 
Previously(21.08) it works fine.

I want to know 2 things
a)the difference of dpdk-pdump between 21.08 and 21.11 (seems bpf changes) 
b)where pcap capture the ring buffer for secondary process?

The output is coming from print_pdump_stats function is zero for 3 parameters.(N.B.1) 
Above parameters are counted on pdump_rxtx function.(it is zero on this function also) 
The ring seems copied under mp_handle (process_msg) or mp_pdump.

P.S.
I understand dpdk-pdump seems to be deprecated by introducing dpdk-dumpcap.

Reference
  https://doc.dpdk.org/guides/prog_guide/pdump_lib.html
  https://doc.dpdk.org/guides/prog_guide/multi_proc_support.html

N.B.1

##### PDUMP DEBUG STATS #####
 -packets dequeued:                     0
 -packets transmitted to vdev:          0
 -packets freed:                        0

Thanks in advance

Atsushi SAKAI

Re: Question about dpdk-pdump ring buffer

[Stephen Hemminger]

On Fri, 8 Apr 2022 06:50:36 +0000
"sakaia@fujitsu.com" <sakaia@fujitsu.com> wrote:

> Question about dpdk-pdump ring buffer
> 
> With updating from 21.08 to 21.11, The packet capture is failed. 
> Previously(21.08) it works fine.
> 
> I want to know 2 things
> a)the difference of dpdk-pdump between 21.08 and 21.11 (seems bpf changes) 
> b)where pcap capture the ring buffer for secondary process?
> 
> The output is coming from print_pdump_stats function is zero for 3 parameters.(N.B.1) 
> Above parameters are counted on pdump_rxtx function.(it is zero on this function also) 
> The ring seems copied under mp_handle (process_msg) or mp_pdump.
> 
> P.S.
> I understand dpdk-pdump seems to be deprecated by introducing dpdk-dumpcap.
> 
> Reference
>   https://doc.dpdk.org/guides/prog_guide/pdump_lib.html
>   https://doc.dpdk.org/guides/prog_guide/multi_proc_support.html
> 
> N.B.1
> 
> ##### PDUMP DEBUG STATS #####
>  -packets dequeued:                     0
>  -packets transmitted to vdev:          0
>  -packets freed:                        0
> 
> Thanks in advance
> 
> Atsushi SAKAI

What is the application, is it built wit 21.11?

Note: You can't mix DPDK versions. The ring is internal structure so both application
and pdump must be built from same version.