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From:   Shakeel Butt <shakeelb@google.com>
Date:   Tue, 22 Jun 2021 11:23:12 -0700
Message-ID: <CALvZod703WD0Ab8EMpd6+JxzhKEjnwZkYRA9VB5LoUmG_yccSQ@mail.gmail.com>
Subject: Re: [PATCH v31 08/13] mm/damon/dbgfs: Export kdamond pid to the user space
To:     SeongJae Park <sj38.park@gmail.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        SeongJae Park <sjpark@amazon.de>, Jonathan.Cameron@huawei.com,
        acme@kernel.org, alexander.shishkin@linux.intel.com,
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        Jonathan Corbet <corbet@lwn.net>,
        David Hildenbrand <david@redhat.com>, dwmw@amazon.com,
        Marco Elver <elver@google.com>, "Du, Fan" <fan.du@intel.com>,
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        Greg Thelen <gthelen@google.com>, guoju.fgj@alibaba-inc.com,
        jgowans@amazon.com, Mel Gorman <mgorman@suse.de>, mheyne@amazon.de,
        Minchan Kim <minchan@kernel.org>,
        Ingo Molnar <mingo@redhat.com>, namhyung@kernel.org,
        "Peter Zijlstra (Intel)" <peterz@infradead.org>,
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        Vlastimil Babka <vbabka@suse.cz>,
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On Mon, Jun 21, 2021 at 1:31 AM SeongJae Park <sj38.park@gmail.com> wrote:
>
> From: SeongJae Park <sjpark@amazon.de>
>
> For CPU usage accounting, knowing pid of the monitoring thread could be
> helpful.  For example, users could use cpuaccount cgroups with the pid.
>
> This commit therefore exports the pid of currently running monitoring
> thread to the user space via 'kdamond_pid' file in the debugfs
> directory.
>
> Signed-off-by: SeongJae Park <sjpark@amazon.de>
> Reviewed-by: Fernand Sieber <sieberf@amazon.com>
> ---

[...]

>
> +static const struct file_operations kdamond_pid_fops = {
> +       .owner = THIS_MODULE,

I don't think you need to set the owner (and for other fops) as these
files are built into modules. Otherwise it looks good.