diff mbox series

[3/6] btrfs: edit prelim_ref_insert() to use rb helpers

Message ID f283c3c32d5c69339c04eafa8d996112f9f6f638.1733850317.git.beckerlee3@gmail.com (mailing list archive)
State New
Headers show
Series reduce boilerplate code within btrfs | expand

Commit Message

Lee Beckermeyer Dec. 10, 2024, 7:06 p.m. UTC 
This commit edits prelim_ref_insert() in fs/btrfs/backref.c to use
rb_find_add_cached(). It also adds a comparison function for use with
rb_find_add_cached().

Signed-off-by: Roger L. Beckermeyer III <beckerlee3@gmail.com>
---
 fs/btrfs/backref.c | 71 +++++++++++++++++++++++-----------------------
 1 file changed, 36 insertions(+), 35 deletions(-)

Comments

David Sterba Dec. 11, 2024, 6:47 p.m. UTC | #1 
On Tue, Dec 10, 2024 at 01:06:09PM -0600, Roger L. Beckermeyer III wrote:
> This commit edits prelim_ref_insert() in fs/btrfs/backref.c to use
> rb_find_add_cached(). It also adds a comparison function for use with
> rb_find_add_cached().
> 
> Signed-off-by: Roger L. Beckermeyer III <beckerlee3@gmail.com>
> ---
>  fs/btrfs/backref.c | 71 +++++++++++++++++++++++-----------------------
>  1 file changed, 36 insertions(+), 35 deletions(-)
> 
> diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
> index 6d9f39c1d89c..fcbcfce0f93a 100644
> --- a/fs/btrfs/backref.c
> +++ b/fs/btrfs/backref.c
> @@ -250,6 +250,17 @@ static int prelim_ref_compare(const struct prelim_ref *ref1,
>  	return 0;
>  }
>  
> +static int prelim_ref_cmp(struct rb_node *node, const struct rb_node *exist)
> +{
> +	int result;
> +	struct prelim_ref *ref1 = rb_entry(node, struct prelim_ref, rbnode);
> +	struct prelim_ref *ref2 = rb_entry(exist, struct prelim_ref, rbnode);

Same type mismatch, missing const.
> +
> +	result = prelim_ref_compare(ref1, ref2);

You don't need the temporary variable 'result'.

> +
> +	return result;
> +}
> +
diff mbox series

Patch

diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index 6d9f39c1d89c..fcbcfce0f93a 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -250,6 +250,17 @@  static int prelim_ref_compare(const struct prelim_ref *ref1,
 	return 0;
 }
 
+static int prelim_ref_cmp(struct rb_node *node, const struct rb_node *exist)
+{
+	int result;
+	struct prelim_ref *ref1 = rb_entry(node, struct prelim_ref, rbnode);
+	struct prelim_ref *ref2 = rb_entry(exist, struct prelim_ref, rbnode);
+
+	result = prelim_ref_compare(ref1, ref2);
+
+	return result;
+}
+
 static void update_share_count(struct share_check *sc, int oldcount,
 			       int newcount, const struct prelim_ref *newref)
 {
@@ -281,52 +292,42 @@  static void prelim_ref_insert(const struct btrfs_fs_info *fs_info,
 	struct rb_node **p;
 	struct rb_node *parent = NULL;
 	struct prelim_ref *ref;
-	int result;
-	bool leftmost = true;
+	struct rb_node *exist;
 
 	root = &preftree->root;
 	p = &root->rb_root.rb_node;
+	parent = *p;
+	ref = rb_entry(parent, struct prelim_ref, rbnode);
 
-	while (*p) {
-		parent = *p;
-		ref = rb_entry(parent, struct prelim_ref, rbnode);
-		result = prelim_ref_compare(ref, newref);
-		if (result < 0) {
-			p = &(*p)->rb_left;
-		} else if (result > 0) {
-			p = &(*p)->rb_right;
-			leftmost = false;
-		} else {
-			/* Identical refs, merge them and free @newref */
-			struct extent_inode_elem *eie = ref->inode_list;
+	exist = rb_find_add_cached(&newref->rbnode, root, prelim_ref_cmp);
+	if (exist != NULL) {
+		/* Identical refs, merge them and free @newref */
+		struct extent_inode_elem *eie = ref->inode_list;
 
-			while (eie && eie->next)
-				eie = eie->next;
+		while (eie && eie->next)
+			eie = eie->next;
 
-			if (!eie)
-				ref->inode_list = newref->inode_list;
-			else
-				eie->next = newref->inode_list;
-			trace_btrfs_prelim_ref_merge(fs_info, ref, newref,
-						     preftree->count);
-			/*
-			 * A delayed ref can have newref->count < 0.
-			 * The ref->count is updated to follow any
-			 * BTRFS_[ADD|DROP]_DELAYED_REF actions.
-			 */
-			update_share_count(sc, ref->count,
-					   ref->count + newref->count, newref);
-			ref->count += newref->count;
-			free_pref(newref);
-			return;
-		}
+		if (!eie)
+			ref->inode_list = newref->inode_list;
+		else
+			eie->next = newref->inode_list;
+		trace_btrfs_prelim_ref_merge(fs_info, ref, newref,
+							preftree->count);
+		/*
+		 * A delayed ref can have newref->count < 0.
+		 * The ref->count is updated to follow any
+		 * BTRFS_[ADD|DROP]_DELAYED_REF actions.
+		 */
+		update_share_count(sc, ref->count,
+					ref->count + newref->count, newref);
+		ref->count += newref->count;
+		free_pref(newref);
+		return;
 	}
 
 	update_share_count(sc, 0, newref->count, newref);
 	preftree->count++;
 	trace_btrfs_prelim_ref_insert(fs_info, newref, NULL, preftree->count);
-	rb_link_node(&newref->rbnode, parent, p);
-	rb_insert_color_cached(&newref->rbnode, root, leftmost);
 }
 
 /*