From: Alex Shi alex.shi@linux.alibaba.com

[ Upstream commit f6131f28057d4fd8922599339e701a2504e0f23d ]

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@linux.alibaba.com Cc: Shuah Khan shuah@kernel.org Cc: Roman Gushchin guro@fb.com Cc: Tejun Heo tj@kernel.org Cc: Mike Rapoport rppt@linux.vnet.ibm.com Cc: Jay Kamat jgkamat@fb.com Cc: linux-kselftest@vger.kernel.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Roman Gushchin guro@fb.com Acked-by: Tejun Heo tj@kernel.org Signed-off-by: Shuah Khan skhan@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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..c19a97dd02d4 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 memory controller\n"); + for (i = 0; i < ARRAY_SIZE(tests); i++) { switch (tests[i].fn(root)) { case KSFT_PASS: