This test fails routinely in our prod testing environment, and I can
reproduce it locally as well.
The test allocates dcache inside a cgroup, then drops the memory limit
and checks that usage drops correspondingly. The reason it fails is
because dentries are freed with an RCU delay - a debugging sleep shows
that usage drops as expected shortly after.
Insert a 1s sleep after dropping the limit. This should be good
enough, assuming that machines running those tests are otherwise not
very busy.
Link: https://lkml.kernel.org/r/20230801135632.1768830-1-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
1813e51eec ("memcg: increase MEMCG_CHARGE_BATCH to 64") has changed
the batch size while this test case has been left behind. This has led
to a test failure reported by test bot:
not ok 2 selftests: cgroup: test_kmem # exit=1
Update the tolerance for the pcp charges to reflect the
MEMCG_CHARGE_BATCH change to fix this.
[akpm@linux-foundation.org: update comments, per Roman]
Link: https://lkml.kernel.org/r/Y4m8Unt6FhWKC6IH@dhcp22.suse.cz
Fixes: 1813e51eec ("memcg: increase MEMCG_CHARGE_BATCH to 64")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: kernel test robot <yujie.liu@intel.com>
Link: https://lore.kernel.org/oe-lkp/202212010958.c1053bd3-yujie.liu@intel.com
Acked-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Tested-by: Yujie Liu <yujie.liu@intel.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Michal Koutný" <mkoutny@suse.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
With memcg having switched to rstat, memory.stat output is precise.
Update the cgroup selftest to reflect the expectations and error
tolerances of the new implementation.
Also add newly tracked types of memory to the memory.stat side of the
equation, since they're included in memory.current and could throw false
positives.
Link: https://lkml.kernel.org/r/20210209163304.77088-9-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Acked-by: Roman Gushchin <guro@fb.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a simple test to check the percpu memory accounting. The test creates
a cgroup tree with 1000 child cgroups and checks values of memory.current
and memory.stat::percpu.
Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Tobin C. Harding <tobin@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Waiman Long <longman@redhat.com>
Cc: Michal Koutný <mkoutny@suse.com>
Cc: Bixuan Cui <cuibixuan@huawei.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Link: http://lkml.kernel.org/r/20200608230819.832349-6-guro@fb.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add some tests to cover the kernel memory accounting functionality. These
are covering some issues (and changes) we had recently.
1) A test which allocates a lot of negative dentries, checks memcg slab
statistics, creates memory pressure by setting memory.max to some low
value and checks that some number of slabs was reclaimed.
2) A test which covers side effects of memcg destruction: it creates
and destroys a large number of sub-cgroups, each containing a
multi-threaded workload which allocates and releases some kernel
memory. Then it checks that the charge ans memory.stats do add up on
the parent level.
3) A test which reads /proc/kpagecgroup and implicitly checks that it
doesn't crash the system.
4) A test which spawns a large number of threads and checks that the
kernel stacks accounting works as expected.
5) A test which checks that living charged slab objects are not
preventing the memory cgroup from being released after being deleted by
a user.
Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Link: http://lkml.kernel.org/r/20200623174037.3951353-19-guro@fb.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
