[PATCH 0/2] cgroup-v2/freezer: small improvements

From: Pavel Tikhomirov

Date: Tue Dec 23 2025 - 05:24:48 EST


This patch series contains two small improvements for cgroup-v2 freezer
controller.

First allows freezing cgroups with kthreads inside, we still won't
freeze kthreads, we still ignore them, but at the same time we allow
cgroup to report frozen when all other non-kthread tasks are frozen.

Second patch adds information into dmesg to identify processes which
prevent cgroup from being frozen or just don't allow it to freeze fast
enough.

I hope these changes will be generally useful for the users of freezer
cgroup controller.

Signed-off-by: Pavel Tikhomirov <ptikhomirov@xxxxxxxxxxxxx>

Pavel Tikhomirov (2):
cgroup-v2/freezer: Allow freezing with kthreads
cgroup-v2/freezer: Print information about unfreezable process

include/linux/cgroup-defs.h | 5 ++
kernel/cgroup/cgroup-internal.h | 5 ++
kernel/cgroup/cgroup.c | 2 +
kernel/cgroup/freezer.c | 155 ++++++++++++++++++++++++++++++--
4 files changed, 161 insertions(+), 6 deletions(-)

--
2.52.0