Make sure that we ignore protection of a memcg that is the target of
memcg reclaim.
Signed-off-by: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
---
tools/testing/selftests/cgroup/test_memcontrol.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/tools/testing/selftests/cgroup/test_memcontrol.c b/tools/testing/selftests/cgroup/test_memcontrol.c
index d4182e94945e..bac3b91f1579 100644
--- a/tools/testing/selftests/cgroup/test_memcontrol.c
+++ b/tools/testing/selftests/cgroup/test_memcontrol.c
@@ -238,6 +238,8 @@ static int cg_test_proc_killed(const char *cgroup)
return -1;
}
+static bool reclaim_until(const char *memcg, long goal_usage);
+
/*
* First, this test creates the following hierarchy:
* A memory.min = 0, memory.max = 200M
@@ -266,6 +268,12 @@ static int cg_test_proc_killed(const char *cgroup)
* unprotected memory in A available, and checks that:
* a) memory.min protects pagecache even in this case,
* b) memory.low allows reclaiming page cache with low events.
+ *
+ * Then we try to reclaim from A/B/C using memory.reclaim until its
+ * usage reaches 10M.
+ * This makes sure that:
+ * (a) We ignore the protection of the reclaim target memcg.
+ * (b) The previously calculated emin value (~29M) should be dismissed.
*/
static int test_memcg_protection(const char *root, bool min)
{
@@ -385,6 +393,9 @@ static int test_memcg_protection(const char *root, bool min)
if (!values_close(cg_read_long(parent[1], "memory.current"), MB(50), 3))
goto cleanup;
+ if (!reclaim_until(children[0], MB(10)))
+ goto cleanup;
+
if (min) {
ret = KSFT_PASS;
goto cleanup;
--
2.38.1.584.g0f3c55d4c2-goog
