On Wed, Apr 19, 2023 at 12:42:39PM -0700, Andrii Nakryiko wrote:
> I won't claim anything for perf, maybe Arnaldo can clarify, but I
> suspect that perf is also meant to be relatively independent from
> specific kernel and work on wide variety of kernels.
Supposedly it is though I've never been able to convince myself to
decouple (and ship the latest perf) for SLE. One reason is documented
userspace functionality that has no backing kernel support which for
an Enterprise distro opens us up to bug reports.
For a while Vince was maintaining a page documenting breakage in the
perf_event ABI but last I checked it ended at V4.0. Not sure if he
just stopped updating, or that's where breakage ended :)
I know how Fedora maintains perf but I keep meaning to look at how
RHEL maintains it. As Michal said our code base is V5.14 for SLE15*
and due to the frequent code-refactoring in perf, backporting perf
userspace fixes for SLE is a real chore unless we agressively maintain
forward porting ("forklifting").
Tony
--
Tony Jones
SUSE Kernel Performance Team
