[LTP] [PATCH v2] cgroup_fj_common.sh: Do not disable systemd related cgroup subsystems

[Xinjian Ma (Fujitsu)]

> Hi Ma,
> 
> > The cpu, io, memory, and pids subsystems under the root cgroup cannot
> > be disabled because they are used for systemd. Currently, the test of
> > cpu and memory subsystems in cgroup_fj_function.sh and
> > cgroup_fj_stress.sh will report the error
> > "echo: write error: device or resource busy".
> 
> Could you please share a bit of info on which system it fails. Do you use cgroup
> v1?

Hi Petr

It fails on Fedora 37 which uses cgroupv2.
cgroupv1 won't trigger this failure.

> 
> Kind regards,
> Petr
> 
> > Reviewed-by: Petr Vorel <pvorel@suse.cz>
> > Signed-off-by: Ma Xinjian <maxj.fnst@fujitsu.com>
> > ---
> >  .../kernel/controllers/cgroup_fj/cgroup_fj_common.sh      | 8 +++++++-
> >  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> > diff --git
> > a/testcases/kernel/controllers/cgroup_fj/cgroup_fj_common.sh
> > b/testcases/kernel/controllers/cgroup_fj/cgroup_fj_common.sh
> > index e866641ba..153d351d7 100755
> > --- a/testcases/kernel/controllers/cgroup_fj/cgroup_fj_common.sh
> > +++ b/testcases/kernel/controllers/cgroup_fj/cgroup_fj_common.sh
> > @@ -77,7 +77,13 @@ common_cleanup()
> 
> >      cgroup_cleanup
> 
> > -    [ "$cgroup_version" = "2" ] && ROD echo "-$subsystem" \>
> "/sys/fs/cgroup/cgroup.subtree_control"
> > +    if [ "$cgroup_version" = "2" ]; then
> > +        case "$subsystem" in
> > +        cpu|io|memory|pids)
> > +            :;;
> > +        *) ROD echo "-$subsystem" \>
> "/sys/fs/cgroup/cgroup.subtree_control";;
> > +        esac
> > +    fi
> >  }
> 
> >  . cgroup_lib.sh