| Message ID | 20250311123640.530377-1-mkoutny@suse.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | cgroup v1 deprecation messages | expand |
> Memory controller had begun to print warning messages when using some > attributes that do no have a counterpart in its cgroup v2 > implementation. This is informative to users who run (unwittingly) on v1 > or to distros that run v1 (they can learn about such users or prepare > for disabling v1 configs). > > I consider the deprecated files in three categories: > - RE) replacement exists, > - DN) dropped as non-ideal concept (e.g. non-hierarchical resources), > - NE) not evaluated (yet). > > For RE, I added the replacement into the warning message, DN have only a > plain deprecation message and I marked the commits with NE as RFC. > Also I'd be happy if you would point out some forgotten knobs that'd > deserve similar warnings. > > The level of messages is info to avoid too much noise (may be increased > in future when there are fewer users). Some knobs from DN have warn > level. > > The net_cls and net_prio controllers that only exist on v1 hierarchies > have no straightforward action for users (replacement would rely on net > NS or eBPF), so messages for their usage are omitted, although it'd be > good to eventually retire that code in favor of aforementioned. > > At the end are some cleanup patches I encountered en route. For the block related parts, as I'm assuming Tejun will pick this up: Acked-by: Jens Axboe <axboe@kernel.dk>
On Tue, Mar 11, 2025 at 01:36:17PM +0100, Michal Koutný wrote: > Memory controller had begun to print warning messages when using some > attributes that do no have a counterpart in its cgroup v2 > implementation. This is informative to users who run (unwittingly) on v1 > or to distros that run v1 (they can learn about such users or prepare > for disabling v1 configs). > > I consider the deprecated files in three categories: > - RE) replacement exists, > - DN) dropped as non-ideal concept (e.g. non-hierarchical resources), > - NE) not evaluated (yet). > > For RE, I added the replacement into the warning message, DN have only a > plain deprecation message and I marked the commits with NE as RFC. > Also I'd be happy if you would point out some forgotten knobs that'd > deserve similar warnings. > > The level of messages is info to avoid too much noise (may be increased > in future when there are fewer users). Some knobs from DN have warn > level. > > The net_cls and net_prio controllers that only exist on v1 hierarchies > have no straightforward action for users (replacement would rely on net > NS or eBPF), so messages for their usage are omitted, although it'd be > good to eventually retire that code in favor of aforementioned. > > At the end are some cleanup patches I encountered en route. Applied to cgroup/for-6.15. Thanks.
Memory controller had begun to print warning messages when using some attributes that do no have a counterpart in its cgroup v2 implementation. This is informative to users who run (unwittingly) on v1 or to distros that run v1 (they can learn about such users or prepare for disabling v1 configs). I consider the deprecated files in three categories: - RE) replacement exists, - DN) dropped as non-ideal concept (e.g. non-hierarchical resources), - NE) not evaluated (yet). For RE, I added the replacement into the warning message, DN have only a plain deprecation message and I marked the commits with NE as RFC. Also I'd be happy if you would point out some forgotten knobs that'd deserve similar warnings. The level of messages is info to avoid too much noise (may be increased in future when there are fewer users). Some knobs from DN have warn level. The net_cls and net_prio controllers that only exist on v1 hierarchies have no straightforward action for users (replacement would rely on net NS or eBPF), so messages for their usage are omitted, although it'd be good to eventually retire that code in favor of aforementioned. At the end are some cleanup patches I encountered en route. Changes from v1 (https://lore.kernel.org/r/20250304153801.597907-1-mkoutny@suse.com/) - cpuset load_balance/pressure warn wording (Waiman) - comment typo (Waiman) - collect Acks - drop bouncing Cc: and respective RFC (self) - change level warn -> info, except for spread slab (Tejun) - add memory.swappiness (self) - add legacy freezer message (self) - update cover wrt net* controllers (self) Michal Koutný (11): cgroup/cpuset-v1: Add deprecation messages to sched_load_balance and memory_pressure_enabled cgroup/cpuset-v1: Add deprecation messages to memory_spread_page and memory_spread_slab cgroup/blkio: Add deprecation messages to reset_stats cgroup: Print message when /proc/cgroups is read on v2-only system cgroup/cpuset-v1: Add deprecation messages to mem_exclusive and mem_hardwall cgroup/cpuset-v1: Add deprecation messages to memory_migrate RFC cgroup/cpuset-v1: Add deprecation messages to sched_relax_domain_level mm: Add transformation message for per-memcg swappiness cgroup: Add deprecation message to legacy freezer controller cgroup: Update file naming comment blk-cgroup: Simplify policy files registration .../cgroup-v1/freezer-subsystem.rst | 4 ++++ .../admin-guide/cgroup-v1/memory.rst | 1 + block/blk-cgroup.c | 8 +++++-- block/blk-ioprio.c | 23 ++++++------------- include/linux/cgroup-defs.h | 5 ++-- include/linux/cgroup.h | 1 + kernel/cgroup/cgroup-internal.h | 1 + kernel/cgroup/cgroup-v1.c | 7 ++++++ kernel/cgroup/cgroup.c | 4 ++-- kernel/cgroup/cpuset-v1.c | 8 +++++++ kernel/cgroup/legacy_freezer.c | 6 +++-- mm/memcontrol-v1.c | 6 +++-- 12 files changed, 47 insertions(+), 27 deletions(-) base-commit: 80e54e84911a923c40d7bee33a34c1b4be148d7a