On Fri, Feb 21, 2020 at 02:20:10PM +0000, Mel Gorman wrote:

I fully acknowledge that this may have value for sysadmins and may be a
good enough reason to merge it for environments that typically build and
configure their own kernels. I doubt that general distributions would
enable it but that's a guess.

OTOH, many sysadmins seem to 'rely' on BPF scripts and other such fancy
things these days.

 ( of course, we have the open question on what happens when we break
   one of those BPF 'important' scripts ... )

My main reservation with this patch is that it exposes, to userspace, an
ABI that is very hard to interpret and subject to implementation
details.

So while it can be disabled; people who have it enabled might suddenly
complain when we change the meaning/interpretation/whatever of these
magic numbers.

Michael; you seem to have ignored the tracepoint / BPF angle earlier in
this discussion; that is not something that could/would work for you?