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

[Petr Vorel]

> > 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.

OK, thx for info, merged!

I managed to reproduce the same issue also on Debian trixie or some Alpine
(which don't use systemd).  I still wonder what could be the root cause, because
many other systemd based systems have no problem (various SLES versions and
openSUSE Tumbleweed).

Kind regards,
Petr

> > 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