+ mm-memcg-__mem_cgroup_remove_exceeded-could-handle-a-on-tree-mz-properly.patch added to -mm tree

+ mm-memcg-__mem_cgroup_remove_exceeded-could-handle-a-on-tree-mz-properly.patch added to -mm tree

[Andrew Morton]

The patch titled
     Subject: mm/memcg: __mem_cgroup_remove_exceeded could handle a !on-tree mz properly
has been added to the -mm tree.  Its filename is
     mm-memcg-__mem_cgroup_remove_exceeded-could-handle-a-on-tree-mz-properly.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-memcg-__mem_cgroup_remove_exceeded-could-handle-a-on-tree-mz-properly.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-memcg-__mem_cgroup_remove_exceeded-could-handle-a-on-tree-mz-properly.patch

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------------------------------------------------------
From: Wei Yang <richard.weiyang@gmail.com>
Subject: mm/memcg: __mem_cgroup_remove_exceeded could handle a !on-tree mz properly

There is no tree operation if mz is not on-tree.

Let's remove the extra check.

Link: https://lkml.kernel.org/r/20220312071623.19050-2-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memcontrol.c |    8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

--- a/mm/memcontrol.c~mm-memcg-__mem_cgroup_remove_exceeded-could-handle-a-on-tree-mz-properly
+++ a/mm/memcontrol.c
@@ -503,9 +503,11 @@ static void mem_cgroup_update_tree(struc
 			unsigned long flags;
 
 			spin_lock_irqsave(&mctz->lock, flags);
-			/* if on-tree, remove it */
-			if (mz->on_tree)
-				__mem_cgroup_remove_exceeded(mz, mctz);
+			/*
+			 * remove it first
+			 * If not on-tree, no tree ops.
+			 */
+			__mem_cgroup_remove_exceeded(mz, mctz);
 			/*
 			 * Insert again. mz->usage_in_excess will be updated.
 			 * If excess is 0, no tree ops.
_

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

mm-memcg-mem_cgroup_per_node-is-already-set-to-0-on-allocation.patch
mm-memcg-retrieve-parent-memcg-from-cssparent.patch
mm-memcg-set-memcg-after-css-verified-and-got-reference.patch
mm-memcg-set-pos-to-prev-unconditionally.patch
mm-memcg-move-generation-assignment-and-comparison-together.patch
mm-memcg-mz-already-removed-from-rb_tree-in-mem_cgroup_largest_soft_limit_node.patch
mm-memcg-__mem_cgroup_remove_exceeded-could-handle-a-on-tree-mz-properly.patch
mm-memcg-add-next_mz-back-to-soft-limit-tree-if-not-reclaimed-yet.patch
mm-page_alloc-add-same-penalty-is-enough-to-get-round-robin-order.patch
mm-page_alloc-add-penalty-to-local_node.patch
memcg-do-not-tweak-node-in-alloc_mem_cgroup_per_node_info.patch