xfs: only walk the incore inode tree once per blockgc scan

Perform background block preallocation gc scans more efficiently by
walking the incore inode tree once.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
This commit is contained in:
Darrick J. Wong 2021-01-22 16:48:43 -08:00
commit 419567534e