xfs: avoid COW fork extent lookups in writeback if the fork didn't change
authorChristoph Hellwig <hch@lst.de>
Tue, 17 Jul 2018 23:51:52 +0000 (16:51 -0700)
committerDarrick J. Wong <darrick.wong@oracle.com>
Tue, 31 Jul 2018 20:18:09 +0000 (13:18 -0700)
commite666aa37f4330cb93a5004a89b7a938312e74e36
tree321bb7db899b5c9f76b6164f8aeaa0ae4f0dad55
parent745b3f76d1c889d738a1c4537a3c491bc1ecac4d
xfs: avoid COW fork extent lookups in writeback if the fork didn't change

Used the per-fork sequence counter to avoid lookups in the writeback code
unless the COW fork actually changed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
fs/xfs/xfs_aops.c
fs/xfs/xfs_iomap.c
fs/xfs/xfs_iomap.h