ext4: mark all metadata I/O with REQ_META
As Dave Chinner pointed out at the 2013 LSF/MM workshop, it's
important that metadata I/O requests are marked as such to avoid
priority inversions caused by I/O bandwidth throttling.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
index 8dcaea6..d0f13ea 100644
--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -441,7 +441,7 @@
trace_ext4_read_block_bitmap_load(sb, block_group);
bh->b_end_io = ext4_end_bitmap_read;
get_bh(bh);
- submit_bh(READ, bh);
+ submit_bh(READ | REQ_META | REQ_PRIO, bh);
return bh;
verify:
ext4_validate_block_bitmap(sb, desc, block_group, bh);