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Date:   Sun, 1 May 2022 16:44:26 +0300
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Subject: Re: [PATCH memcg v4] net: set proper memcg for net_init hooks
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To:     Shakeel Butt <shakeelb@google.com>,
        Roman Gushchin <roman.gushchin@linux.dev>
Cc:     =?UTF-8?Q?Michal_Koutn=c3=bd?= <mkoutny@suse.com>,
        Vlastimil Babka <vbabka@suse.cz>, kernel@openvz.org,
        Florian Westphal <fw@strlen.de>,
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        Michal Hocko <mhocko@suse.com>,
        Cgroups <cgroups@vger.kernel.org>,
        netdev <netdev@vger.kernel.org>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>
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From:   Vasily Averin <vvs@openvz.org>
In-Reply-To: <CALvZod5HugCO2G3+Av3pXC6s2sy0zKW_HRaRyhOO9GOOWV1SsQ@mail.gmail.com>
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On 4/28/22 01:47, Shakeel Butt wrote:
> On Wed, Apr 27, 2022 at 3:43 PM Vasily Averin <vvs@openvz.org> wrote:
>>
>> On 4/27/22 18:06, Shakeel Butt wrote:
>>> On Wed, Apr 27, 2022 at 5:22 AM Michal Koutný <mkoutny@suse.com> wrote:
>>>>
>>>> On Tue, Apr 26, 2022 at 10:23:32PM -0700, Shakeel Butt <shakeelb@google.com> 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