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Date:   Tue, 19 Nov 2019 18:17:52 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Namjae Jeon <namjae.jeon@samsung.com>
Cc:     'Daniel Wagner' <dwagner@suse.de>, linux-kernel@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, gregkh@linuxfoundation.org,
        valdis.kletnieks@vt.edu, hch@lst.de, linkinjeon@gmail.com,
        Markus.Elfring@web.de, sj1557.seo@samsung.com
Subject: Re: [PATCH v2 02/13] exfat: add super block operations
Message-ID: <20191119171752.GA20042@lst.de>
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On Tue, Nov 19, 2019 at 06:22:28PM +0900, Namjae Jeon wrote:
> > No idea what the code does. But I was just skimming over and find the
> > above pattern somehow strange. Shouldn't this be something like
> Right.
> 
> > 
> > 	if (!READ_ONCE(sbi->s_dirt)) {
> > 		WRITE_ONCE(sbi->s_dirt, true);
> 
> It should be :
> 	if (READ_ONCE(sbi->s_dirt)) {
>  		WRITE_ONCE(sbi->s_dirt, false);
> I will fix it on v3.

The other option would be to an unsigned long flags field and define
bits flags on it, then use test_and_set_bit, test_and_clear_bit etc.
Which might be closer to the pattern we use elsewhere in the kernel.