[PATCH 6/7] pcapng: add user-supplied timestamp support

[Stephen Hemminger]

On Wed, 29 Apr 2026 03:31:10 -0400
Dawid Wesierski <dawid.wesierski at intel.com> wrote:

> From: Marek Kasiewicz <marek.kasiewicz at intel.com>
> 
> Add rte_pcapng_copy_ts() which accepts an optional timestamp parameter
> in nanoseconds. When the timestamp is non-zero, it is used directly
> instead of reading the TSC. This allows applications to provide
> hardware PTP timestamps from the NIC, enabling accurate packet capture
> with PTP-domain timing rather than host-local TSC values.


Also, the HW timestamp would have to be in ns since Unix Epoch
not what HW clock is. That is a hard thing to do...

I would rather have the pcapng infrastructure know how to use
hardware timestamp dynamic field if present. But the problem is
getting the conversion right; it would have to compute offset and
resolution per NIC, and NIC's roll over too fast. The problem is
hard.

Bottom line: needs lots more work