how to enable lib_pdump?

how to enable lib_pdump?

[Jon Ross]

dpdk-dumpcap works fine w/ dpdk-testpmd running, but I can't get it to
work while my app is running.

The docs say to do it the way testmpd does it. But testpmd does...
everything? It's hard to tell what's needed to get capture working.

The only reference to anything related to lib_pdump in testpmd is the
call to rte_pdump_init(). But adding this call seems to have no
effect.

Just to make sure "it's not me" I added the call to the
examples/skeleton app, and dpdk-dumpcap will not run w/ the modified
sample app. So it seems like it's more than just calling
rte_pdump_init(). Can anyone shed some light on what needs to happen
to get an app working w/ dpdk-dumpcap?

I'm using dpdk version v21.11, compile from source via github.

Thanks,
-Jon

Re: how to enable lib_pdump?

[Stephen Hemminger]

On Tue, 18 Jan 2022 10:42:16 -0800
Jon Ross <jonross@gmail.com> wrote:

> dpdk-dumpcap works fine w/ dpdk-testpmd running, but I can't get it to
> work while my app is running.
> 
> The docs say to do it the way testmpd does it. But testpmd does...
> everything? It's hard to tell what's needed to get capture working.
>
You need at a minimum:
  1. primary/secondary process support
  2. ethedev rx/tx callbacks enabled
  3. rte_pdump_init() called in primary
  4. enough shared memory (huge pages) for additional copies.

> The only reference to anything related to lib_pdump in testpmd is the
> call to rte_pdump_init(). But adding this call seems to have no
> effect.
> 
> Just to make sure "it's not me" I added the call to the
> examples/skeleton app, and dpdk-dumpcap will not run w/ the modified
> sample app. So it seems like it's more than just calling
> rte_pdump_init(). Can anyone shed some light on what needs to happen
> to get an app working w/ dpdk-dumpcap?
> 
> I'm using dpdk version v21.11, compile from source via github.
> 
> Thanks,
> -Jon


Most failures are because of doing something that breaks primary/secondary
process support. Like using --in-memory or having a device that won't support
primary/secondary.