On Tue, 10 Sep 2019 11:42:06 -0700
Joe Perches [off-list ref] wrote:

On Tue, 2019-09-10 at 14:26 -0400, Steven Rostedt wrote:

quoted

On Tue, 10 Sep 2019 10:18:44 -0700
Joe Perches [off-list ref] wrote:
  

quoted

quoted

It's not just for the lastest kernel. We must maintain backward
compatibility here too. If there use to be a usage of this, then we
must keep it until the kernels are no longer used (perhaps 7 years?)    

That argues for not using "%pfw" at all for some number of years.

Perhaps the '%pfw' should be '%pnfw' for 'name' and 'fwnode'  

  -ENOCOMPREHENSION  

Perhaps you were not copied on the whole series.

https://lore.kernel.org/lkml/20190910084707.18380-1-sakari.ailus@linux.intel.com/ (local)

Thanks for the link.

As I understand it, Sakair Ailus is proposing to
obsolete the current vsprintf "%p[Ff]" extension
and replace the usage with a new "%pfw" extension
which would emit the name of a pointer to "struct fwnode {}".

https://lore.kernel.org/lkml/20190910084707.18380-10-sakari.ailus@linux.intel.com/ (local)

If reusing "%pf<foo>" is a problem, then instead
it might be reasonable to have a new "%pn<foo>" for
that use instead.

btw:

Is there kernel version information available in
trace output files?

Not really. This is just a library that parses the trace event formats,
there's not kernel versions passed in, but we do use variations in
formats and such to determine what is supported.

If so, it might be reasonable to change the tooling
there instead.

Actually, I think we could just look to see if "%pfw" is used and fall
to that, otherwise consider it an older kernel and do it the original
way.

-- Steve