xfs: store xfs_mount in the buftarg instead of in the xfs_buf
Each buffer contains both a buftarg pointer and a mount pointer. If
we add a mount pointer into the buftarg, we can avoid needing the
b_mount field in every buffer and grab it from the buftarg when
needed instead. This shrinks the xfs_buf by 8 bytes.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
diff --git a/fs/xfs/linux-2.6/xfs_buf.c b/fs/xfs/linux-2.6/xfs_buf.c
index 22c7bff..d692897 100644
--- a/fs/xfs/linux-2.6/xfs_buf.c
+++ b/fs/xfs/linux-2.6/xfs_buf.c
@@ -894,7 +894,7 @@
trace_xfs_buf_lock(bp, _RET_IP_);
if (atomic_read(&bp->b_pin_count) && (bp->b_flags & XBF_STALE))
- xfs_log_force(bp->b_mount, 0);
+ xfs_log_force(bp->b_target->bt_mount, 0);
if (atomic_read(&bp->b_io_remaining))
blk_run_address_space(bp->b_target->bt_mapping);
down(&bp->b_sema);
@@ -1017,7 +1017,6 @@
{
int error;
- bp->b_mount = mp;
bp->b_flags |= XBF_WRITE;
bp->b_flags &= ~(XBF_ASYNC | XBF_READ);
@@ -1038,8 +1037,6 @@
{
trace_xfs_buf_bdwrite(bp, _RET_IP_);
- bp->b_mount = mp;
-
bp->b_flags &= ~XBF_READ;
bp->b_flags |= (XBF_DELWRI | XBF_ASYNC);
@@ -1128,7 +1125,7 @@
xfs_bdstrat_cb(
struct xfs_buf *bp)
{
- if (XFS_FORCED_SHUTDOWN(bp->b_mount)) {
+ if (XFS_FORCED_SHUTDOWN(bp->b_target->bt_mount)) {
trace_xfs_bdstrat_shut(bp, _RET_IP_);
/*
* Metadata write that didn't get logged but
@@ -1644,6 +1641,7 @@
xfs_buftarg_t *
xfs_alloc_buftarg(
+ struct xfs_mount *mp,
struct block_device *bdev,
int external,
const char *fsname)
@@ -1652,6 +1650,7 @@
btp = kmem_zalloc(sizeof(*btp), KM_SLEEP);
+ btp->bt_mount = mp;
btp->bt_dev = bdev->bd_dev;
btp->bt_bdev = bdev;
if (xfs_setsize_buftarg_early(btp, bdev))