Btrfs: use cached state when dirtying pages during buffered write

During a buffered IO write, we can have an extent state that we got when
we locked the range (if the range starts at an offset lower than eof), so
always pass it to btrfs_dirty_pages() so that setting the delalloc bit
in the range does not need to do a full search in the inode's io tree,
saving time and reducing the amount of time we hold the io tree's lock.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 16c8031db645fa74ed9836bb2bf2265d2184e133..cba2ac371ce014a6a194fe64e1f9757039332bce 100644 (file)
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1755,7 +1755,7 @@ static noinline ssize_t __btrfs_buffered_write(struct file *file,
 
                if (copied > 0)
                        ret = btrfs_dirty_pages(inode, pages, dirty_pages,
-                                               pos, copied, NULL);
+                                               pos, copied, &cached_state);
                if (extents_locked)
                        unlock_extent_cached(&BTRFS_I(inode)->io_tree,
                                             lockstart, lockend, &cached_state);