[LTP] [PATCH] controllers/cpuset: Make mount failure TCONF

[Petr Vorel]

> Hi!
> > > It appears that if the subsystem is available under V2 then mounting
> > > the V1 can fail. Probably when the V2 has processes assigned to a
> > > group it controls.

> > Sounds likely, but it would be good to check this in the kernel code or with
> > kernel cgroup developers.

> I'm pretty sure that controller can be used either in v1, or in v2 but
> not from both at the same time by choice. Some of the changes between v1
> and v2 are incompatible so this couldn't work either way.

> I think that once the controller name is written to
> /sys/fs/cgroup/unified/cgroup.subtree_controll mounting it to v1 should
> fail, so maybe we should just try to grep the fail instead and exit the
> test with TCONF if we found the controller bound to v2 already.

Sounds like a good idea.

Kind regards,
Petr