From f5f92630f752f32ce10c855527d767c0398f2532 Mon Sep 17 00:00:00 2001
From: Shakeel Butt <shakeel.butt@linux.dev>
Date: Thu, 15 Aug 2024 08:54:02 -0700
Subject: [PATCH] memcg: replace memcg ID idr with xarray

fix error path in mem_cgroup_alloc(), per Dan

Link: https://lkml.kernel.org/r/20240815155402.3630804-1-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Suggested-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Muchun Song <muchun.song@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 mm/memcontrol.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index d4622e600e15..cb2996d5d3f4 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3496,16 +3496,17 @@ static struct mem_cgroup *mem_cgroup_alloc(struct mem_cgroup *parent)
 	struct mem_cgroup *memcg;
 	int node, cpu;
 	int __maybe_unused i;
-	long error = -ENOMEM;
+	long error;
 
 	memcg = kzalloc(struct_size(memcg, nodeinfo, nr_node_ids), GFP_KERNEL);
 	if (!memcg)
-		return ERR_PTR(error);
+		return ERR_PTR(-ENOMEM);
 
 	error = xa_alloc(&mem_cgroup_ids, &memcg->id.id, NULL,
 			 XA_LIMIT(1, MEM_CGROUP_ID_MAX), GFP_KERNEL);
 	if (error)
 		goto fail;
+	error = -ENOMEM;
 
 	memcg->vmstats = kzalloc(sizeof(struct memcg_vmstats),
 				 GFP_KERNEL_ACCOUNT);
-- 
2.50.1