xfs: set XBF_DONE on newly formatted btree block that are ready for writing

Source kernel commit: c1e0f8e6fb060b23b6f1b82eb4265983f7d271f8

The btree bulkloading code calls xfs_buf_delwri_queue_here when it has
finished formatting a new btree block and wants to queue it to be
written to disk.  Once the new btree root has been committed, the blocks
(and hence the buffers) will be accessible to the rest of the
filesystem.  Mark each new buffer as DONE when adding it to the delwri
list so that the next btree traversal can skip reloading the contents
from disk.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bill O'Donnell <bodonnel@redhat.com>

diff --git a/libxfs/xfs_btree_staging.c b/libxfs/xfs_btree_staging.c
index baf7f422603e5fe29bf9bc279cc393183988ce12..ae2d9c63f4846a038fa942d841bef418d5abaf1f 100644 (file)
--- a/libxfs/xfs_btree_staging.c
+++ b/libxfs/xfs_btree_staging.c
@@ -342,6 +342,12 @@ xfs_btree_bload_drop_buf(
        if (*bpp == NULL)
                return;
 
+       /*
+        * Mark this buffer XBF_DONE (i.e. uptodate) so that a subsequent
+        * xfs_buf_read will not pointlessly reread the contents from the disk.
+        */
+       (*bpp)->b_flags |= XBF_DONE;
+
        xfs_buf_delwri_queue_here(*bpp, buffers_list);
        xfs_buf_relse(*bpp);
        *bpp = NULL;