The cgroup testing relies on the root cgroup's subtree_control setting, If the 'memory' controller isn't set, all test cases will be failed as following: $ sudo ./test_memcontrol not ok 1 test_memcg_subtree_control not ok 2 test_memcg_current ok 3 # skip test_memcg_min not ok 4 test_memcg_low not ok 5 test_memcg_high not ok 6 test_memcg_max not ok 7 test_memcg_oom_events ok 8 # skip test_memcg_swap_max not ok 9 test_memcg_sock not ok 10 test_memcg_oom_group_leaf_events not ok 11 test_memcg_oom_group_parent_events not ok 12 test_memcg_oom_group_score_events To correct this unexpected failure, this patch write the 'memory' to subtree_control of root to get a right result. Signed-off-by: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx> Cc: Shuah Khan <shuah@xxxxxxxxxx> Cc: Roman Gushchin <guro@xxxxxx> Cc: Tejun Heo <tj@xxxxxxxxxx> Cc: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx> Cc: Jay Kamat <jgkamat@xxxxxx> Cc: linux-kselftest@xxxxxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx Reviewed-by: Roman Gushchin <guro@xxxxxx> --- tools/testing/selftests/cgroup/test_memcontrol.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/tools/testing/selftests/cgroup/test_memcontrol.c b/tools/testing/selftests/cgroup/test_memcontrol.c index 6f339882a6ca..73612d604a2a 100644 --- a/tools/testing/selftests/cgroup/test_memcontrol.c +++ b/tools/testing/selftests/cgroup/test_memcontrol.c @@ -1205,6 +1205,10 @@ int main(int argc, char **argv) if (cg_read_strstr(root, "cgroup.controllers", "memory")) ksft_exit_skip("memory controller isn't available\n"); + if (cg_read_strstr(root, "cgroup.subtree_control", "memory")) + if (cg_write(root, "cgroup.subtree_control", "+memory")) + ksft_exit_skip("Failed to set root memory controller\n"); + for (i = 0; i < ARRAY_SIZE(tests); i++) { switch (tests[i].fn(root)) { case KSFT_PASS: -- 2.19.1.856.g8858448bb