[v3,1/3] kselftest/cgroup: fix unexpected testing failure on test_memcontrol

Commit Message

Alex Shi May 27, 2019, 6:28 a.m. UTC

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 <[e-mail]>
Cc: Shuah Khan <[e-mail]>
Cc: Roman Gushchin <[e-mail]>
Cc: Tejun Heo <[e-mail]>
Cc: Mike Rapoport <[e-mail]>
Cc: Jay Kamat <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Reviewed-by: Roman Gushchin <[e-mail]>
Acked-by: Tejun Heo <[e-mail]>
---
 tools/testing/selftests/cgroup/test_memcontrol.c | 4 ++++
 1 file changed, 4 insertions(+)

Patch

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: