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

["Michal Koutný" <mkoutny-IBi9RG/b67k@public.gmane.org>]

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