Re: [PATCH v7 05/12] fs: allow to always dirty inode in __generic_write_end

From: "Andreas Grünbacher" <andreas.gruenbacher@gmail.com>
To: Christoph Hellwig <hch@lst.de>
Cc: Andreas Gruenbacher <agruenba@redhat.com>,
	cluster-devel <cluster-devel@redhat.com>,
	Linux FS-devel Mailing List <linux-fsdevel@vger.kernel.org>
Subject: Re: [PATCH v7 05/12] fs: allow to always dirty inode in __generic_write_end
Date: Mon, 4 Jun 2018 18:24:21 +0200	[thread overview]
Message-ID: <CAHpGcMJNRpwrpSa+r465JsUpExVb7TcBY784Ptdz79ciOQMXjg@mail.gmail.com> (raw)
In-Reply-To: <20180604124850.GA30780@lst.de>

2018-06-04 14:48 GMT+02:00 Christoph Hellwig <hch@lst.de>:
> On Mon, Jun 04, 2018 at 02:37:22PM +0200, Andreas Gruenbacher wrote:
>> @@ -2106,7 +2105,7 @@ int __generic_write_end(struct inode *inode, loff_t pos, unsigned copied,
>>        * ordering of page lock and transaction start for journaling
>>        * filesystems.
>>        */
>> -     if (i_size_changed)
>> +     if (dirty_inode)
>>               mark_inode_dirty(inode);
>>       return copied;
>
> Calling mark_inode_dirty on an already dirty inode is cheap, so how
> about just calling it directly in your caller that always wants to
> set the inode dirty?

The dirty_inode hook is where gfs2 converts the in-core inode into the
on-disk format (the equivalent of xfs_inode_to_disk), so it's not
quite that cheap. I realize this could be done differently in gfs2,
but that's not where we stand today, and I really can't fix ten things
all at the same time.

Thanks,
Andreas