Re: [PATCH 5/6] xfs: merge xfs_reclaim_inodes_ag into xfs_inode_walk_ag

["Darrick J. Wong" <djwong@kernel.org>]

On Fri, Mar 26, 2021 at 06:30:56AM +0000, Christoph Hellwig wrote:
> On Thu, Mar 25, 2021 at 05:21:40PM -0700, Darrick J. Wong wrote:
> > From: Darrick J. Wong <djwong@kernel.org>
> > 
> > Merge these two inode walk loops together, since they're pretty similar
> > now.  Get rid of XFS_ICI_NO_TAG since nobody uses it.
> 
> The laster user of XFS_ICI_NO_TAG was quotoff, and the last reference
> was removed in "xfs: remove indirect calls from xfs_inode_walk{,_ag}".
> So I think it should be dropped there, or even better in a prep patch
> removing all the XFS_ICI_NO_TAG code before that one.

Ok, moved to patch 3.

> > +static inline bool
> > +selected_for_walk(
> > +	unsigned int		tag,
> > +	struct xfs_inode	*ip)
> > +{
> > +	switch (tag) {
> > +	case XFS_ICI_BLOCKGC_TAG:
> > +		return xfs_blockgc_grab(ip);
> > +	case XFS_ICI_RECLAIM_TAG:
> > +		return xfs_reclaim_inode_grab(ip);
> > +	default:
> > +		return false;
> > +	}
> > +}
> 
> Maybe name ths something that starts with xfs_ and ends with _grab?

xfs_grabbed_for_walk?

> >   * and release all incore inodes with the given radix tree @tag.
> > @@ -786,12 +803,14 @@ xfs_inode_walk_ag(
> >  	bool			done;
> >  	int			nr_found;
> >  
> > -	ASSERT(tag == XFS_ICI_BLOCKGC_TAG);
> > +	ASSERT(tag < RADIX_TREE_MAX_TAGS);
> >  
> >  restart:
> >  	done = false;
> >  	skipped = 0;
> >  	first_index = 0;
> > +	if (tag == XFS_ICI_RECLAIM_TAG)
> > +		first_index = READ_ONCE(pag->pag_ici_reclaim_cursor);
> 
> if / else to make this clear?

Done.

> >  		for (i = 0; i < nr_found; i++) {
> >  			if (!batch[i])
> >  				continue;
> > -			error = xfs_blockgc_scan_inode(batch[i], eofb);
> > -			xfs_irele(batch[i]);
> > +			switch (tag) {
> > +			case XFS_ICI_BLOCKGC_TAG:
> > +				error = xfs_blockgc_scan_inode(batch[i], eofb);
> > +				xfs_irele(batch[i]);
> > +				break;
> > +			case XFS_ICI_RECLAIM_TAG:
> > +				xfs_reclaim_inode(batch[i], pag);
> > +				error = 0;
> 
> Maybe move the irele into xfs_blockgc_scan_inode to make the calling
> conventions more similar?

Ok.  I'll also fix the off-by-one error in the nr_to_scan check.

--D