commit 9d64272cd3be2aae71f89f7ababbee90a7587b33
author Chris Mason <chris.mason@oracle.com> Tue Apr 03 11:43:19 2007 -0400
committer David Woodhouse <dwmw2@hera.kernel.org> Tue Apr 03 11:43:19 2007 -0400
tree 1b610106cefd177ef8e76e55e4d054c729255832
parent 2da566edd8ce32ae2952b863ee634bcc2e7d63c1

Btrfs: don't wait on uptodate buffers on read

Signed-off-by: Chris Mason <chris.mason@oracle.com>

fs/btrfs/disk-io.c

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 39b117a..055cd45 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -214,6 +214,8 @@
 	bh = btrfs_find_create_tree_block(root, blocknr);
 	if (!bh)
 		return bh;
+	if (buffer_uptodate(bh))
+		goto uptodate;
 	lock_buffer(bh);
 	if (!buffer_uptodate(bh)) {
 		get_bh(bh);
@@ -226,6 +228,7 @@
 	} else {
 		unlock_buffer(bh);
 	}
+uptodate:
 	if (check_tree_block(root, bh))
 		BUG();
 	return bh;