From 76828c882630ced08b5ddce22cc0095b05de9bc5 Mon Sep 17 00:00:00 2001
From: Theodore Ts'o <tytso@mit.edu>
Date: Mon, 15 Jul 2013 12:27:47 -0400
Subject: [PATCH] ext4: yield during large unlinks
During large unlink operations on files with extents, we can use a lot
of CPU time. This adds a cond_resched() call when starting to examine
the next level of a multi-level extent tree. Multi-level extent trees
are rare in the first place, and this should rarely be executed.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
---
fs/ext4/extents.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 593091537e76..cfdc51e30257 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -2835,6 +2835,9 @@ again:
err = -EIO;
break;
}
+ /* Yield here to deal with large extent trees.
+ * Should be a no-op if we did IO above. */
+ cond_resched();
if (WARN_ON(i + 1 > depth)) {
err = -EIO;
break;