Re: [PATCH v4 3/6] net/nfb: update timestamp calculation to meaningful value

Martin Spinler
2026-01-27T08:12:16Z

On Wed, 2026-01-21 at 09:33 -0800, Stephen Hemminger wrote:
> The patch is ok as far as it goes.
>
> But the best practice in DPDK for drivers doing timestamps is for
> the driver to only put a timestamp on if timestamp offload flag
> was set when configuring that device. For the case of multiple devices
> that means that one device may have timestamp and other not.

Ack. I'll work it in.

> Also any driver that supports receive timestamp must provide
> a read_clock operation. Otherwise the application has no way of knowing
> what units the timestamp is in. I added that to the AI review
> script so new drivers will get rejected with out it.

Ack.

> I suspect that in this drivers case it is only used in systems where:
> - only single instance of device is possible
> - your application is just assuming a common unit like nanosecond.

You're right.

More responses in another email thread.