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Date:   Fri, 12 Mar 2021 15:49:18 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Daeho Jeong <daeho43@gmail.com>
Cc:     linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net, kernel-team@android.com,
        Daeho Jeong <daehojeong@google.com>
Subject: Re: [PATCH v4] f2fs: add sysfs nodes to get runtime compression stat
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On Fri, Mar 12, 2021 at 11:42:04PM +0900, Daeho Jeong wrote:
> So, do you want we protect the values here with spin_lock and just
> read without spin_lock in sysfs read part?

I would not use any lock at all if this were my code.  Remember, this is
for debugging/information only, right?  And the data is always "stale"
so what is it going to be used for?

thanks,

greg k-h