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Sender: Minchan Kim <minchan.kim@gmail.com>
Date:   Mon, 8 Feb 2021 20:19:02 -0800
From:   Minchan Kim <minchan@kernel.org>
To:     John Hubbard <jhubbard@nvidia.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        linux-mm <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>, gregkh@linuxfoundation.org,
        surenb@google.com, joaodias@google.com, willy@infradead.org
Subject: Re: [PATCH v2] mm: cma: support sysfs
Message-ID: <YCINNpA09FTwr63U@google.com>
References: <20210208180142.2765456-1-minchan@kernel.org>
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 <43cd6fc4-5bc5-50ec-0252-ffe09afd68ea@nvidia.com>
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Precedence: bulk

On Mon, Feb 08, 2021 at 05:57:17PM -0800, John Hubbard wrote:
> On 2/8/21 3:36 PM, Minchan Kim wrote:
> ...
> > > >    	char name[CMA_MAX_NAME];
> > > > +#ifdef CONFIG_CMA_SYSFS
> > > > +	struct cma_stat	*stat;
> > > 
> > > This should not be a pointer. By making it a pointer, you've added a bunch of pointless
> > > extra code to the implementation.
> > 
> > Originally, I went with the object lifetime with struct cma as you
> > suggested to make code simple. However, Greg KH wanted to have
> > release for kobj_type since it is consistent with other kboject
> > handling.
> 
> Are you talking about the kobj in your new struct cma_stat? That seems
> like circular logic if so. I'm guessing Greg just wanted kobj methods
> to be used *if* you are dealing with kobjects. That's a narrower point.
> 
> I can't imagine that he would have insisted on having additional
> allocations just so that kobj freeing methods could be used. :)

I have no objection if Greg agree static kobject is okay in this
case. Greg?