[PATCH 3/3] ext4: Find desired extent in ext4_ext_shift_extents() using binsearch
From: Roman Pen <hidden>
Date: 2017-01-02 12:55:14
Also in:
lkml
Subsystem:
ext4 file system, filesystems (vfs and infrastructure), the rest · Maintainers:
"Theodore Ts'o", Alexander Viro, Christian Brauner, Linus Torvalds
The aim of this patch is to optimize a search of an extent while doing right shift using binsearch. Cc: Namjae Jeon <redacted> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: linux-ext4@vger.kernel.org Cc: linux-kernel@vger.kernel.org --- fs/ext4/extents.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 9fbf92ca358c..f65cc2762780 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c@@ -5433,10 +5433,15 @@ ext4_ext_shift_extents(struct inode *inode, handle_t *handle, else /* Beginning is reached, end of the loop */ iterator = NULL; - /* Update path extent in case we need to stop */ - while (le32_to_cpu(extent->ee_block) < start) - extent++; - path[depth].p_ext = extent; + if (le32_to_cpu(extent->ee_block) < start) + /* + * Desired extent is somewhere in the middle, + * do binsearch and update a path with it. + */ + ext4_ext_binsearch(inode, &path[depth], start); + else + /* Set the first extent */ + path[depth].p_ext = extent; } ret = ext4_ext_shift_path_extents(path, shift, inode, handle, SHIFT);
--
2.10.2