[PATCH 6/6] track redirty_tail() calls

[Fengguang Wu <wfg@mail.ustc.edu.cn>]

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It helps a lot to know how redirty_tail() are called.

Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
---
 fs/fs-writeback.c |   10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

--- linux-2.6.23-rc2-mm2.orig/fs/fs-writeback.c
+++ linux-2.6.23-rc2-mm2/fs/fs-writeback.c
@@ -210,6 +210,11 @@ static int write_inode(struct inode *ino
 	return 0;
 }
 
+#define redirty_tail(inode)						\
+	do {								\
+		__redirty_tail(inode, __LINE__);			\
+	} while (0)
+
 /*
  * Redirty an inode: set its when-it-was dirtied timestamp and move it to the
  * furthest end of its superblock's dirty-inode list.
@@ -219,11 +224,14 @@ static int write_inode(struct inode *ino
  * the case then the inode must have been redirtied while it was being written
  * out and we don't reset its dirtied_when.
  */
-static void redirty_tail(struct inode *inode)
+static void __redirty_tail(struct inode *inode, int line)
 {
 	struct super_block *sb = inode->i_sb;
 
 	check_dirty_inode(inode);
+	if (unlikely(sysctl_inode_debug))
+		printk(KERN_DEBUG "redirtied inode %lu line %d\n",
+				inode->i_ino, line);
 	inode->dirtied_when = jiffies;
 	list_move(&inode->i_list, &sb->s_dirty);
 	check_dirty_inode(inode);

--