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Date:   Thu, 23 Nov 2023 08:15:47 +0000
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Subject: Re: [PATCH v2 1/2] mm: memcg: print out cgroup name in the memcg tracepoints
From:   Shakeel Butt <shakeelb@google.com>
To:     Dmitry Rokosov <ddrokosov@salutedevices.com>
Cc:     rostedt@goodmis.org, mhiramat@kernel.org, hannes@cmpxchg.org,
        mhocko@kernel.org, roman.gushchin@linux.dev, muchun.song@linux.dev,
        akpm@linux-foundation.org, kernel@sberdevices.ru,
        rockosov@gmail.com, cgroups@vger.kernel.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, bpf@vger.kernel.org
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On Thu, Nov 23, 2023 at 11:03:34AM +0300, Dmitry Rokosov wrote:
[...]
> > > +		cgroup_name(memcg->css.cgroup,
> > > +			__entry->name,
> > > +			sizeof(__entry->name));
> > 
> > Any reason not to use cgroup_ino? cgroup_name may conflict and be
> > ambiguous.
> 
> I actually didn't consider it, as the cgroup name serves as a clear tag
> for filtering the appropriate cgroup in the entire trace file. However,
> you are correct that there might be conflicts with cgroup names.
> Therefore, it might be better to display both tags: ino and name. What
> do you think on this?
> 

I can see putting cgroup name can avoid pre or post processing, so
putting both are fine. Though keep in mind that cgroup_name acquires a
lock which may impact the applications running on the system.