Re: [PATCH memcg v4] net: set proper memcg for net_init hooks allocations

From: Vasily Averin
Date: Sun May 01 2022 - 09:44:42 EST


On 4/28/22 01:47, Shakeel Butt wrote:
> On Wed, Apr 27, 2022 at 3:43 PM Vasily Averin <vvs@xxxxxxxxxx> wrote:
>>
>> On 4/27/22 18:06, Shakeel Butt wrote:
>>> On Wed, Apr 27, 2022 at 5:22 AM Michal Koutný <mkoutny@xxxxxxxx> wrote:
>>>>
>>>> On Tue, Apr 26, 2022 at 10:23:32PM -0700, Shakeel Butt <shakeelb@xxxxxxxxxx> wrote:
>>>>> [...]
>>>>>>
>>>>>> +static inline struct mem_cgroup *get_mem_cgroup_from_obj(void *p)
>>>>>> +{
>>>>>> + struct mem_cgroup *memcg;
>>>>>> +
>>>>>
>>>>> Do we need memcg_kmem_enabled() check here or maybe
>>>>> mem_cgroup_from_obj() should be doing memcg_kmem_enabled() instead of
>>>>> mem_cgroup_disabled() as we can have "cgroup.memory=nokmem" boot
>>>>> param.
>>
>> Shakeel, unfortunately I'm not ready to answer this question right now.
>> I even did not noticed that memcg_kmem_enabled() and mem_cgroup_disabled()
>> have a different nature.
>> If you have no objections I'm going to keep this place as is and investigate
>> this question later.
>>
>
> Patch is good as is. Just add the documentation to the functions in
> the next version and you can keep the ACKs.

I noticed that the kernel already has a function get_mem_cgroup_from_objcg(),
the name of which is very similar to my new function get_mem_cgroup_from_obj().
Maybe it's better to rename my function to get_mem_cgroup_from_ptr()?

Thank you,
Vasily Averin