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Sender: Minchan Kim <minchan.kim@gmail.com>
Date: Mon, 26 Mar 2018 18:57:12 +0900
From: Minchan Kim <minchan@kernel.org>
To: Greg KH <gregkh@linuxfoundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 2/2] zram: idle memory tracking
Message-ID: <20180326095712.GA214483@rodete-desktop-imager.corp.google.com>
References: <20180326064951.123940-1-minchan@kernel.org>
 <20180326064951.123940-2-minchan@kernel.org>
 <20180326081511.GA15432@kroah.com>
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On Mon, Mar 26, 2018 at 10:15:11AM +0200, Greg KH wrote:
> On Mon, Mar 26, 2018 at 03:49:51PM +0900, Minchan Kim wrote:
> > +static int zram_debugfs_register(struct zram *zram)
> > +{
> > +	struct dentry *ret;
> > +
> > +	if (!zram_debugfs_root)
> > +		return -ENOENT;
> 
> No need to care, you should not error out if debugfs is not enabled or
> not working, your code path should be identical either way.  debugfs is
> not required for any functionality, so don't treat it like it matters :)

Glad to hear. It makes code much clean.

> 
> > +	zram->debugfs_dir = debugfs_create_dir(zram->disk->disk_name,
> > +						zram_debugfs_root);
> > +	if (!zram->debugfs_dir)
> > +		return -ENOMEM;
> 
> No need to check the return value of any debugfs call, you can always
> either use it for future debugfs calls, or ignore it.
> 
> > +	ret = debugfs_create_file("access_time", 0400, zram->debugfs_dir,
> > +				zram, &proc_zram_access_operations);
> > +	if (!ret)
> > +		return -ENOMEM;
> 
> Again, you shouldn't care :)
> 
> > +
> > +	return 0;
> 
> just return void, no need to test any of this.

Thanks for the quick review, Greg.