[PATCH 4/4] selftests: memcg: Remove protection from top level memcg

Michal Koutný
2022-05-13T17:18:11Z

The reclaim is triggered by memory limit in a subtree, therefore the
testcase does not need configured protection against external reclaim.

Also, correct/deduplicate respective comments

Signed-off-by: Michal Koutn√Ω <mkoutny-IBi9RG/b67k@public.gmane.org>
---
tools/testing/selftests/cgroup/test_memcontrol.c | 12 ++++--------
1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/tools/testing/selftests/cgroup/test_memcontrol.c b/tools/testing/selftests/cgroup/test_memcontrol.c
index 9ffacf024bbd..9d370aafd799 100644
--- a/tools/testing/selftests/cgroup/test_memcontrol.c
+++ b/tools/testing/selftests/cgroup/test_memcontrol.c
@@ -247,7 +247,7 @@ static int cg_test_proc_killed(const char *cgroup)

/*
* First, this test creates the following hierarchy:
- * A memory.min = 50M, memory.max = 200M
+ * A memory.min = 0, memory.max = 200M
* A/B memory.min = 50M, memory.current = 50M
* A/B/C memory.min = 75M, memory.current = 50M
* A/B/D memory.min = 25M, memory.current = 50M
@@ -257,7 +257,7 @@ static int cg_test_proc_killed(const char *cgroup)
* Usages are pagecache, but the test keeps a running
* process in every leaf cgroup.
* Then it creates A/G and creates a significant
- * memory pressure in it.
+ * memory pressure in A.
*
* A/B memory.current ~= 50M
* A/B/C memory.current ~= 29M
@@ -335,8 +335,6 @@ static int test_memcg_min(const char *root)
(void *)(long)fd);
}

- if (cg_write(parent[0], "memory.min", "50M"))
- goto cleanup;
if (cg_write(parent[1], "memory.min", "50M"))
goto cleanup;
if (cg_write(children[0], "memory.min", "75M"))
@@ -404,8 +402,8 @@ static int test_memcg_min(const char *root)

/*
* First, this test creates the following hierarchy:
- * A memory.low = 50M, memory.max = 200M
- * A/B memory.low = 50M, memory.current = 50M
+ * A memory.low = 0, memory.max = 200M
+ * A/B memory.low = 50M, memory.current = ...
* A/B/C memory.low = 75M, memory.current = 50M
* A/B/D memory.low = 25M, memory.current = 50M
* A/B/E memory.low = 0, memory.current = 50M
@@ -490,8 +488,6 @@ static int test_memcg_low(const char *root)
goto cleanup;
}

- if (cg_write(parent[0], "memory.low", "50M"))
- goto cleanup;
if (cg_write(parent[1], "memory.low", "50M"))
goto cleanup;
if (cg_write(children[0], "memory.low", "75M"))
--
2.35.3