linux/kernel/cgroup
Tejun Heo 52478777b3 cgroup: Add cgroup_task_notifier and task migration events
A subsystem can attach to the cgroup hierarchy itself, independent of which
controllers are enabled where - BPF hooks already behave this way and
sched_ext sub-schedulers do too. Controller callbacks can't track task
migrations for them: sched_ext must re-home a task whose migration crosses a
sub-scheduler boundary, but the cpu controller's attach callbacks fire only
when the task_group changes and miss moves whenever the controller topology
is coarser than the sub-scheduler topology.

Add cgroup_task_notifier with per-task migration events mirroring the
can_attach/attach/cancel_attach phases so that a consumer which prepares
per-task state can also veto a migration: CGROUP_TASK_MIGRATING fires
pre-commit, CGROUP_TASK_MIGRATED post-commit and
CGROUP_TASK_MIGRATE_CANCELED unwinds a failed migration. Only migrations
that change a task's dfl cgroup are reported.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
2026-07-19 21:10:56 -10:00
..
cgroup-internal.h cgroup: Expose some cgroup helpers 2026-03-05 18:15:58 -10:00
cgroup-v1.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
cgroup.c cgroup: Add cgroup_task_notifier and task migration events 2026-07-19 21:10:56 -10:00
cpuset-internal.h cgroup/cpuset: Reserve DL bandwidth only for root-domain moves 2026-05-11 10:27:14 -10:00
cpuset-v1.c cgroup: Inline cgroup_has_tasks() in cgroup.h 2026-05-15 07:24:12 -10:00
cpuset.c cgroup: Changes for v7.2 2026-06-17 12:03:56 +01:00
debug.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
dmem.c cgroup/dmem: Return -ENOMEM on failed pool preallocation 2026-05-10 15:43:46 -10:00
freezer.c cgroup: cgroup.stat.local time accounting 2025-08-22 07:50:43 -10:00
legacy_freezer.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
Makefile kernel/cgroup: Add "dmem" memory accounting cgroup 2025-01-06 17:24:38 +01:00
misc.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
namespace.c treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21 01:02:28 -08:00
pids.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
rdma.c cgroup/rdma: Drop unnecessary READ_ONCE() on event counters 2026-05-18 09:24:50 -10:00
rstat.c cgroup: rstat: relax NMI guard after switch to try_cmpxchg 2026-05-20 09:44:35 -10:00