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

[Kirill Tkhai]

On 31.01.2020 18:47, Michal Hocko wrote:
> 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.

Hm, why isn't the same scheme used in alloc_mem_cgroup_per_node_info() then?

Kirill