2024-05-06 13:43:48

by Xiu Jianfeng

Subject: [PATCH -next] mm: memcg: use meaningful error code for return value

alloc_mem_cgroup_per_node_info() returns 1 if failed, use -ENOMEM
instead, which is more meaningful.

Signed-off-by: Xiu Jianfeng <[email protected]>
---
mm/memcontrol.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index d11536ef59ef..657f68b536c4 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -5659,7 +5659,7 @@ static int alloc_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node)

pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, node);
if (!pn)
- return 1;
+ return -ENOMEM;

pn->lruvec_stats = kzalloc_node(sizeof(struct lruvec_stats), GFP_KERNEL,
node);
@@ -5679,7 +5679,7 @@ static int alloc_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node)
fail:
kfree(pn->lruvec_stats);
kfree(pn);
- return 1;
+ return -ENOMEM;
}

static void free_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node)
--
2.34.1

2024-05-06 13:54:02

by Matthew Wilcox

Subject: Re: [PATCH -next] mm: memcg: use meaningful error code for return value

On Mon, May 06, 2024 at 01:36:43PM +0000, Xiu Jianfeng wrote:
> alloc_mem_cgroup_per_node_info() returns 1 if failed, use -ENOMEM
> instead, which is more meaningful.

This should probably be changed to return true/false instead of
an int.

2024-05-06 14:49:50

by Michal Hocko

Subject: Re: [PATCH -next] mm: memcg: use meaningful error code for return value

On Mon 06-05-24 14:53:47, Matthew Wilcox wrote:
> On Mon, May 06, 2024 at 01:36:43PM +0000, Xiu Jianfeng wrote:
> > alloc_mem_cgroup_per_node_info() returns 1 if failed, use -ENOMEM
> > instead, which is more meaningful.
>
> This should probably be changed to return true/false instead of
> an int.

Agreed. Or change the only caller to consume the error. Changing to bool
seems like the easiest way.

--
Michal Hocko
SUSE Labs

2024-05-07 11:17:55

by Xiu Jianfeng

Subject: Re: [PATCH -next] mm: memcg: use meaningful error code for return value

On 2024/5/6 21:53, Matthew Wilcox wrote:
> On Mon, May 06, 2024 at 01:36:43PM +0000, Xiu Jianfeng wrote:
>> alloc_mem_cgroup_per_node_info() returns 1 if failed, use -ENOMEM
>> instead, which is more meaningful.
>
> This should probably be changed to return true/false instead of
> an int.
>
OK, already sent v2.