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References: <20220128203950.3371061-1-namhyung@kernel.org> <2db9fab4-0aff-b8b0-5012-13556ea496af@linux.intel.com>
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From:   Namhyung Kim <namhyung@kernel.org>
Date:   Tue, 1 Feb 2022 12:01:49 -0800
Message-ID: <CAM9d7ciUqaZ02AV4xiknhyAKx0U-4GYKNGJWCa0P=5_CdpxoLg@mail.gmail.com>
Subject: Re: [PATCH 0/3] Handle chroot tasks properly (v1)
To:     Andi Kleen <ak@linux.intel.com>
Cc:     Arnaldo Carvalho de Melo <acme@kernel.org>,
        Jiri Olsa <jolsa@redhat.com>, Ingo Molnar <mingo@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Ian Rogers <irogers@google.com>
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Hi Andi,

On Mon, Jan 31, 2022 at 5:16 PM Andi Kleen <ak@linux.intel.com> wrote:
>
>
> On 1/28/2022 12:39 PM, Namhyung Kim wrote:
> > Hello,
> >
> > I found that perf tools don't work well with tasks in a chroot.  The
> > filenames in MMAP record are from the root directory of the task so
> > it's different than what it sees from outside.
>
>
> While that's a real problem, and for chroot it can be fixed, it's much
> more complicated for the more complex container namespace case with
> custom mounts, including loop back, etc.

Probably.  Note that perf tool can handle namespaces (to some extent)
but missed chroot support.  I have a bug report because of this issue.
Let's fix the simple case first.

>
> It seems it really need some kind of agent to handle all cases. For
> example the agent could understand container metadata formats and then
> do the right thing.

Sounds like a good idea for a long term solution.

Thanks,
Namhyung