Subject: Re: What ixgbe devices support HWTSTAMP_FILTER_ALL for hardware time stamping?

From: Richard Cochran <[email-masked]>
Date: Sat, 14 May 2016 22:26:53 +0200

On Sat, May 14, 2016 at 11:47:22AM -0700, Guy Harris wrote:
> So if you have a GUI application for packet capture, with a combo box to select the type of time stamping, should it:
> 
> 	1) regardless of whether ETHTOOL_GET_TS_INFO is available, open the adapter, try each of the time stamp types to see whether it works, and show a combo box based on that;
> 
> 	2) use ETHTOOL_GET_TS_INFO if available;
> 
> 	3) offer all possibilities regardless of whether they work with the adapter or not, and just report an error for possibilities that don't work?
> 
> My preference is 2) - which is the main reason why libpcap offers "what possibilities are available?" APIs, not just "request this possibility" APIs.

You are going to have to implement #1 in any case, if you want your
program to work on all kernels.  IIRC get_ts_info appeared in 3.5.

Thanks,
Richard