From cef2193729595686f787c5858aad69b4369de757 Mon Sep 17 00:00:00 2001
From: Filipe David Borba Manana <fdmanana@gmail.com>
Date: Mon, 2 Sep 2013 12:19:13 +0100
Subject: [PATCH] Btrfs: more efficient inode tree replace operation

Instead of removing the current inode from the red black tree
and then add the new one, just use the red black tree replace
operation, which is more efficient.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Reviewed-by: Zach Brown <zab@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
---
 fs/btrfs/inode.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 6091ba9d24941..abed81d936873 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4688,11 +4688,11 @@ static void inode_tree_add(struct inode *inode)
 	struct btrfs_inode *entry;
 	struct rb_node **p;
 	struct rb_node *parent;
+	struct rb_node *new = &BTRFS_I(inode)->rb_node;
 	u64 ino = btrfs_ino(inode);
 
 	if (inode_unhashed(inode))
 		return;
-again:
 	parent = NULL;
 	spin_lock(&root->inode_lock);
 	p = &root->inode_tree.rb_node;
@@ -4707,14 +4707,14 @@ static void inode_tree_add(struct inode *inode)
 		else {
 			WARN_ON(!(entry->vfs_inode.i_state &
 				  (I_WILL_FREE | I_FREEING)));
-			rb_erase(parent, &root->inode_tree);
+			rb_replace_node(parent, new, &root->inode_tree);
 			RB_CLEAR_NODE(parent);
 			spin_unlock(&root->inode_lock);
-			goto again;
+			return;
 		}
 	}
-	rb_link_node(&BTRFS_I(inode)->rb_node, parent, p);
-	rb_insert_color(&BTRFS_I(inode)->rb_node, &root->inode_tree);
+	rb_link_node(new, parent, p);
+	rb_insert_color(new, &root->inode_tree);
 	spin_unlock(&root->inode_lock);
 }
 
-- 
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