+ mm-memcg-non-hierarchical-mode-is-deprecated.patch added to -mm tree

+ mm-memcg-non-hierarchical-mode-is-deprecated.patch added to -mm tree

[Andrew Morton]

The patch titled
     Subject: mm/memcg: non-hierarchical mode is deprecated
has been added to the -mm tree.  Its filename is
     mm-memcg-non-hierarchical-mode-is-deprecated.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-memcg-non-hierarchical-mode-is-deprecated.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-memcg-non-hierarchical-mode-is-deprecated.patch

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------------------------------------------------------
From: Wei Yang <richard.weiyang@gmail.com>
Subject: mm/memcg: non-hierarchical mode is deprecated

After commit bef8620cd8e0 ("mm: memcg: deprecate the non-hierarchical
mode"), we won't have a NULL parent except root_mem_cgroup.  And this case
is handled when (memcg == root).

Link: https://lkml.kernel.org/r/20220403020833.26164-1-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memcontrol.c |    3 ---
 1 file changed, 3 deletions(-)

--- a/mm/memcontrol.c~mm-memcg-non-hierarchical-mode-is-deprecated
+++ a/mm/memcontrol.c
@@ -6588,9 +6588,6 @@ void mem_cgroup_calculate_protection(str
 		return;
 
 	parent = parent_mem_cgroup(memcg);
-	/* No parent means a non-hierarchical mode on v1 memcg */
-	if (!parent)
-		return;
 
 	if (parent == root) {
 		memcg->memory.emin = READ_ONCE(memcg->memory.min);
_

Patches currently in -mm which might be from richard.weiyang@gmail.com are

mm-memcg-mz-already-removed-from-rb_tree-if-not-null.patch
mm-memcg-set-memcg-after-css-verified-and-got-reference.patch
mm-memcg-set-pos-explicitly-for-reclaim-and-reclaim.patch
mm-memcg-move-generation-assignment-and-comparison-together.patch
mm-memcg-non-hierarchical-mode-is-deprecated.patch
mm-page_alloc-add-same-penalty-is-enough-to-get-round-robin-order.patch
mm-vmscan-reclaim-only-affects-managed_zones.patch
mm-vmscan-make-sure-wakeup_kswapd-with-managed-zone.patch
mm-vmscan-make-sure-wakeup_kswapd-with-managed-zone-v2.patch
mm-vmscan-sc-reclaim_idx-must-be-a-valid-zone-index.patch