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Message-ID: <30bf8eb7-f039-48cf-3dca-11f99604e12e@suse.cz>
Date:   Wed, 18 Oct 2023 16:11:26 +0200
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Subject: Re: [PATCH v3 2/5] mm: kmem: add direct objcg pointer to task_struct
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From:   Vlastimil Babka <vbabka@suse.cz>
To:     Roman Gushchin <roman.gushchin@linux.dev>,
        Andrew Morton <akpm@linux-foundation.org>
Cc:     linux-kernel@vger.kernel.org, cgroups@vger.kernel.org,
        Johannes Weiner <hannes@cmpxchg.org>,
        Michal Hocko <mhocko@kernel.org>, shakeelb@google.com,
        Muchun Song <muchun.song@linux.dev>,
        Dennis Zhou <dennis@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Naresh Kamboju <naresh.kamboju@linaro.org>
References: <20231016221900.4031141-1-roman.gushchin@linux.dev>
 <20231016221900.4031141-3-roman.gushchin@linux.dev>
 <d698b8d0-1697-e336-bccb-592e633e8b98@suse.cz>
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On 10/18/23 11:52, Vlastimil Babka wrote:
>> +
>> +	return objcg;
>> +}
>> +
>>  __always_inline struct obj_cgroup *get_obj_cgroup_from_current(void)
>>  {
>>  	struct mem_cgroup *memcg;
>> @@ -3008,19 +3054,26 @@ __always_inline struct obj_cgroup *get_obj_cgroup_from_current(void)
>>  
>>  	if (in_task()) {
>>  		memcg = current->active_memcg;
>> +		if (unlikely(memcg))
>> +			goto from_memcg;
>>  
>> -		/* Memcg to charge can't be determined. */
>> -		if (likely(!memcg) && (!current->mm || (current->flags & PF_KTHREAD)))
> The checks for current->mm and PF_KTHREAD seem to be gone completely after
> the patch, was that intended and why?

And also they are not present in the new flavor that's current_obj_cgroup().