[merged mm-stable] mm-zsmalloc-fix-class-per-fullness-zspage-counts.patch removed from -mm tree

[merged mm-stable] mm-zsmalloc-fix-class-per-fullness-zspage-counts.patch removed from -mm tree

[Andrew Morton]

The quilt patch titled
     Subject: mm/zsmalloc: clarify class per-fullness zspage counts
has been removed from the -mm tree.  Its filename was
     mm-zsmalloc-fix-class-per-fullness-zspage-counts.patch

This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: Chengming Zhou <chengming.zhou@linux.dev>
Subject: mm/zsmalloc: clarify class per-fullness zspage counts
Date: Thu, 27 Jun 2024 15:59:58 +0800

We always use insert_zspage() and remove_zspage() to update zspage's
fullness location, which will account correctly.

But this special async free path use "splice" instead of remove_zspage(),
so the per-fullness zspage count for ZS_INUSE_RATIO_0 won't decrease.

Clean things up by decreasing when iterate over the zspage free list.

This doesn't actually fix anything.  ZS_INUSE_RATIO_0 is just a
"placeholder" which is never used anywhere.

Link: https://lkml.kernel.org/r/20240627075959.611783-1-chengming.zhou@linux.dev
Signed-off-by: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/zsmalloc.c |    1 +
 1 file changed, 1 insertion(+)

--- a/mm/zsmalloc.c~mm-zsmalloc-fix-class-per-fullness-zspage-counts
+++ a/mm/zsmalloc.c
@@ -1883,6 +1883,7 @@ static void async_free_zspage(struct wor
 
 		class = zspage_class(pool, zspage);
 		spin_lock(&class->lock);
+		class_stat_dec(class, ZS_INUSE_RATIO_0, 1);
 		__free_zspage(pool, class, zspage);
 		spin_unlock(&class->lock);
 	}
_

Patches currently in -mm which might be from chengming.zhou@linux.dev are