Ferruh Yigit wrote:
> Why timestamp offloading become useless? When timestamp offloading enabled,
> device fills 'mbuf.timestamp' and you can use it.
But the frequency is unknown, and the reference time neither. So it can be used 
only to know that "some time passed" between packets.

> For your case this timestamp for mlx is device clock and you are adding this 
> API
> to be able to convert device clock to real time, this is not something enables
> the timestamp offload.
I get your point, but a keyboard is highly required to use a computer. It's 
pretty much useless without it. Without this API, the timestamp offload makes 
no sense. It's a random number generator at best...

> Technically driver can set the 'mbuf.timestamp' with the real clock right, if 
> it
> is required? Or this can be defined by a devarg?
I don't think so. Device have no sense of system time. And doing it in the 
driver is tricky because it depends on the user needs. Catch-up with NTP 
updates would need a timer and various parameters... Hence we prefer to give a 
simple working code, and users may do this if they want.


For the other comments it's not my call... I would just underline that 
timestamp offload is not usable in the current state, and there is a lot of use 
case for monitoring latency-sensitive applications.

Tom

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