Re: [PATCH] make HWLAT_DETECTOR kernel config either disabled or a module, never builtin.

[John Kacur <jkacur@redhat.com>]

----- Original Message -----
> * Joakim Hernberg | 2015-12-13 11:39:35 [+0100]:
> 
> >I looked at the IRC logs from when this was discussed.  The hwlatdetect
> >script looks for the kernel module and will fail if it's built-in (or
> >compressed).  Also this quote from irc: <jkacur> I need to look
> >at the code, but offhand, I think we said, it cannot be a built-in by design
> 
> Why can't it work by design in built-in mode? The module parameters
> `enabled` and `threshold` can be set via debugfs (and via command line).
> So I don't see here the difference between module and built-in.
> Is there something I missed?
> 
> If the hwlatdetect script is not able to handle that then it deserves to
> be fixed. The same goes for support of compressed modules.
> 
> >These were the reasons for the patch.
> 

The script can be made to handle it, that's not a big deal. I think the historical
reason was worrying that people could be accidentally running a kernel with
some really heavy weight debugging that would affect performance. However, let people
hang themselves if they want. Clark was going to send a patch to allow it, but probably
ran out of time before the holidays. You can beat him to the punch if you want, or wait
for him.

John