From 14ae60c71221d3ec64482476262e5b9eb4494be4 Mon Sep 17 00:00:00 2001 From: "Roger L. Beckermeyer III" Date: Wed, 18 Dec 2024 08:28:52 +1030 Subject: [PATCH] btrfs: update prelim_ref_insert() to use rb helpers Update prelim_ref_insert() to use rb_find_add_cached(). There is a special change that the existing prelim_ref_compare() is called with the first parameter as the existing ref in the rbtree. But the newer rb_find_add_cached() expects the cmp() function to have the first parameter as the to-be-added node, thus the new helper prelim_ref_rb_add_cmp() need to adapt this new order. Signed-off-by: Roger L. Beckermeyer III Reviewed-by: Qu Wenruo Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/backref.c | 79 +++++++++++++++++++++++----------------------- 1 file changed, 39 insertions(+), 40 deletions(-) diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c index 6d9f39c1d89c..3d3923cfc357 100644 --- a/fs/btrfs/backref.c +++ b/fs/btrfs/backref.c @@ -250,6 +250,21 @@ static int prelim_ref_compare(const struct prelim_ref *ref1, return 0; } +static int prelim_ref_rb_add_cmp(const struct rb_node *new, + const struct rb_node *exist) +{ + const struct prelim_ref *ref_new = + rb_entry(new, struct prelim_ref, rbnode); + const struct prelim_ref *ref_exist = + rb_entry(exist, struct prelim_ref, rbnode); + + /* + * prelim_ref_compare() expects the first parameter as the existing one, + * different from the rb_find_add_cached() order. + */ + return prelim_ref_compare(ref_exist, ref_new); +} + static void update_share_count(struct share_check *sc, int oldcount, int newcount, const struct prelim_ref *newref) { @@ -278,55 +293,39 @@ static void prelim_ref_insert(const struct btrfs_fs_info *fs_info, struct share_check *sc) { struct rb_root_cached *root; - 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; + exist = rb_find_add_cached(&newref->rbnode, root, prelim_ref_rb_add_cmp); + if (exist) { + struct prelim_ref *ref = rb_entry(exist, struct prelim_ref, rbnode); + /* Identical refs, merge them and free @newref */ + struct extent_inode_elem *eie = ref->inode_list; - 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; + 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); } /*