+ selftests-memcg-remove-protection-from-top-level-memcg.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

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The patch titled
     Subject: selftests: memcg: remove protection from top level memcg
has been added to the -mm mm-unstable branch.  Its filename is
     selftests-memcg-remove-protection-from-top-level-memcg.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-memcg-remove-protection-from-top-level-memcg.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Michal Koutný <mkoutny@suse.com>
Subject: selftests: memcg: remove protection from top level memcg
Date: Fri, 13 May 2022 19:18:11 +0200

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.

Link: https://lkml.kernel.org/r/20220513171811.730-5-mkoutny@suse.com
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Richard Palethorpe <rpalethorpe@suse.de>
Cc: David Vernet <void@manifault.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 tools/testing/selftests/cgroup/test_memcontrol.c |   12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

--- a/tools/testing/selftests/cgroup/test_memcontrol.c~selftests-memcg-remove-protection-from-top-level-memcg
+++ a/tools/testing/selftests/cgroup/test_memcontrol.c
@@ -247,7 +247,7 @@ static int cg_test_proc_killed(const cha
 
 /*
  * 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 cha
  * 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 *ro
 			      (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 @@ cleanup:
 
 /*
  * 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 *ro
 			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"))
_

Patches currently in -mm which might be from mkoutny@suse.com are

selftests-memcg-fix-compilation.patch
selftests-memcg-expect-no-low-events-in-unprotected-sibling.patch
selftests-memcg-adjust-expected-reclaim-values-of-protected-cgroups.patch
selftests-memcg-remove-protection-from-top-level-memcg.patch