+ mm-memcg-set-memcg-after-css-verified-and-got-reference.patch added to -mm tree

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

The patch titled
     Subject: mm/memcg: set memcg after css verified and got reference
has been added to the -mm tree.  Its filename is
     mm-memcg-set-memcg-after-css-verified-and-got-reference.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-memcg-set-memcg-after-css-verified-and-got-reference.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-memcg-set-memcg-after-css-verified-and-got-reference.patch

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------------------------------------------------------
From: Wei Yang <richard.weiyang@gmail.com>
Subject: mm/memcg: set memcg after css verified and got reference

Patch series "mm/memcg: some cleanup for mem_cgroup_iter()".


This patch (of 3):

Instead of resetting memcg when css is either not verified or has no
reference, we can set it after these are processed.

No functional change, just simplified the code a little.

Link: https://lkml.kernel.org/r/20220225003437.12620-2-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: 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 |   11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

--- a/mm/memcontrol.c~mm-memcg-set-memcg-after-css-verified-and-got-reference
+++ a/mm/memcontrol.c
@@ -1040,15 +1040,10 @@ struct mem_cgroup *mem_cgroup_iter(struc
 		 * is provided by the caller, so we know it's alive
 		 * and kicking, and don't take an extra reference.
 		 */
-		memcg = mem_cgroup_from_css(css);
-
-		if (css == &root->css)
-			break;
-
-		if (css_tryget(css))
+		if (css == &root->css || css_tryget(css)) {
+			memcg = mem_cgroup_from_css(css);
 			break;
-
-		memcg = NULL;
+		}
 	}
 
 	if (reclaim) {
_

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-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