Re: [PATCH 9/9] xfs: add in-memory iunlink log item

[Dave Chinner <david@fromorbit.com>]

On Wed, Jun 29, 2022 at 12:25:53AM -0700, Christoph Hellwig wrote:
> On Mon, Jun 27, 2022 at 10:43:36AM +1000, Dave Chinner wrote:
> > TO do this, we introduce a new in-memory log item to track the
> 
> s/To/To/
> 
> > This allows us to pass the xfs_inode to the transaction commit code
> > along with the modification to be made, and then order the logged
> > modifications via the ->iop_sort and ->iop_precommit operations
> > for the new log item type. As this is an in-memory log item, it
> > doesn't have formatting, CIL or AIL operational hooks - it exists
> > purely to run the inode unlink modifications and is then removed
> > from the transaction item list and freed once the precommit
> > operation has run.
> 
> Do we need to document the fact that we now have purely in-memory log
> items better somewhere?  I see how this works, but it its a little
> non-obvious.

We already have in-memory log items, just not explicitly named. That
is, the transaction delta structures for the superblock and dquot
modifications.

I eventually want to move them to in-memory log items to get all the
special case code for them out of the transaction commit path, and
then add in-memory log items for AGF and AGI header modifications so
that we can move away from AG header buffer locking to serialise AG
specific operations...

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com