Re: [PATCH v2] mm: Allocate shrinker_map on appropriate NUMA node

[Michal Hocko]

On Fri 31-01-20 18:00:51, Kirill Tkhai wrote:
[...]
> @@ -333,8 +333,9 @@ static int memcg_expand_one_shrinker_map(struct mem_cgroup *memcg,
>  		/* Not yet online memcg */
>  		if (!old)
>  			return 0;
> -
> -		new = kvmalloc(sizeof(*new) + size, GFP_KERNEL);
> +		/* See comment in alloc_mem_cgroup_per_node_info()*/
> +		tmp = node_state(nid, N_NORMAL_MEMORY) ? nid : NUMA_NO_NODE;
> +		new = kvmalloc_node(sizeof(*new) + size, GFP_KERNEL, tmp);
>  		if (!new)
>  			return -ENOMEM;

I do not think this is a good pattern to copy. Why cannot you simply use
kvmalloc_node with the given node? The allocator should fallback to the
closest node if the given one doesn't have any memory.
-- 
Michal Hocko
SUSE Labs