rb_erase(&head->href_node, &delayed_refs->href_root);
} else {
assert_spin_locked(&head->lock);
- rb_erase(&ref->rb_node, &head->ref_root);
+ list_del(&ref->list);
}
ref->in_tree = 0;
btrfs_put_delayed_ref(ref);
return done;
}
-void btrfs_merge_delayed_refs(struct btrfs_trans_handle *trans,
- struct btrfs_fs_info *fs_info,
- struct btrfs_delayed_ref_root *delayed_refs,
- struct btrfs_delayed_ref_head *head)
-{
- struct rb_node *node;
- u64 seq = 0;
-
- assert_spin_locked(&head->lock);
- /*
- * We don't have too much refs to merge in the case of delayed data
- * refs.
- */
- if (head->is_data)
- return;
-
- spin_lock(&fs_info->tree_mod_seq_lock);
- if (!list_empty(&fs_info->tree_mod_seq_list)) {
- struct seq_list *elem;
-
- elem = list_first_entry(&fs_info->tree_mod_seq_list,
- struct seq_list, list);
- seq = elem->seq;
- }
- spin_unlock(&fs_info->tree_mod_seq_lock);
-
- node = rb_first(&head->ref_root);
- while (node) {
- struct btrfs_delayed_ref_node *ref;
-
- ref = rb_entry(node, struct btrfs_delayed_ref_node,
- rb_node);
- /* We can't merge refs that are outside of our seq count */
- if (seq && ref->seq >= seq)
- break;
- if (merge_ref(trans, delayed_refs, head, ref, seq))
- node = rb_first(&head->ref_root);
- else
- node = rb_next(&ref->rb_node);
- }
-}
-
int btrfs_check_delayed_seq(struct btrfs_fs_info *fs_info,
struct btrfs_delayed_ref_root *delayed_refs,
u64 seq)
}
}
+/*
+ * Helper to insert the ref_node to the tail or merge with tail.
+ *
+ * Return 0 for insert.
+ * Return >0 for merge.
+ */
+static int
+add_delayed_ref_tail_merge(struct btrfs_trans_handle *trans,
+ struct btrfs_delayed_ref_root *root,
+ struct btrfs_delayed_ref_head *href,
+ struct btrfs_delayed_ref_node *ref)
+{
+ struct btrfs_delayed_ref_node *exist;
+ int mod;
+ int ret = 0;
+
+ spin_lock(&href->lock);
+ /* Check whether we can merge the tail node with ref */
+ if (list_empty(&href->ref_list))
+ goto add_tail;
+ exist = list_entry(href->ref_list.prev, struct btrfs_delayed_ref_node,
+ list);
+ /* No need to compare bytenr nor is_head */
+ if (exist->type != ref->type || exist->no_quota != ref->no_quota ||
+ exist->seq != ref->seq)
+ goto add_tail;
+
+ if ((exist->type == BTRFS_TREE_BLOCK_REF_KEY ||
+ exist->type == BTRFS_SHARED_BLOCK_REF_KEY) &&
+ comp_tree_refs(btrfs_delayed_node_to_tree_ref(exist),
+ btrfs_delayed_node_to_tree_ref(ref),
+ ref->type))
+ goto add_tail;
+ if ((exist->type == BTRFS_EXTENT_DATA_REF_KEY ||
+ exist->type == BTRFS_SHARED_DATA_REF_KEY) &&
+ comp_data_refs(btrfs_delayed_node_to_data_ref(exist),
+ btrfs_delayed_node_to_data_ref(ref)))
+ goto add_tail;
+
+ /* Now we are sure we can merge */
+ ret = 1;
+ if (exist->action == ref->action) {
+ mod = ref->ref_mod;
+ } else {
+ /* Need to change action */
+ if (exist->ref_mod < ref->ref_mod) {
+ exist->action = ref->action;
+ mod = -exist->ref_mod;
+ exist->ref_mod = ref->ref_mod;
+ } else
+ mod = -ref->ref_mod;
+ }
+ exist->ref_mod += mod;
+
+ /* remove existing tail if its ref_mod is zero */
+ if (exist->ref_mod == 0)
+ drop_delayed_ref(trans, root, href, exist);
+ spin_unlock(&href->lock);
+ return ret;
+
+add_tail:
+ list_add_tail(&ref->list, &href->ref_list);
+ atomic_inc(&root->num_entries);
+ trans->delayed_ref_updates++;
+ spin_unlock(&href->lock);
+ return ret;
+}
+
/*
* helper function to update the accounting in the head ref
* existing and update must have the same bytenr
head_ref = btrfs_delayed_node_to_head(ref);
head_ref->must_insert_reserved = must_insert_reserved;
head_ref->is_data = is_data;
- head_ref->ref_root = RB_ROOT;
+ INIT_LIST_HEAD(&head_ref->ref_list);
head_ref->processing = 0;
head_ref->total_ref_mod = count_mod;
u64 num_bytes, u64 parent, u64 ref_root, int level,
int action, int no_quota)
{
- struct btrfs_delayed_ref_node *existing;
struct btrfs_delayed_tree_ref *full_ref;
struct btrfs_delayed_ref_root *delayed_refs;
u64 seq = 0;
+ int ret;
if (action == BTRFS_ADD_DELAYED_EXTENT)
action = BTRFS_ADD_DELAYED_REF;
trace_add_delayed_tree_ref(ref, full_ref, action);
- spin_lock(&head_ref->lock);
- existing = tree_insert(&head_ref->ref_root, &ref->rb_node);
- if (existing) {
- update_existing_ref(trans, delayed_refs, head_ref, existing,
- ref);
- /*
- * we've updated the existing ref, free the newly
- * allocated ref
- */
+ ret = add_delayed_ref_tail_merge(trans, delayed_refs, head_ref, ref);
+
+ /*
+ * XXX: memory should be freed at the same level allocated.
+ * But bad practice is anywhere... Follow it now. Need cleanup.
+ */
+ if (ret > 0)
kmem_cache_free(btrfs_delayed_tree_ref_cachep, full_ref);
- } else {
- atomic_inc(&delayed_refs->num_entries);
- trans->delayed_ref_updates++;
- }
- spin_unlock(&head_ref->lock);
}
/*
u64 num_bytes, u64 parent, u64 ref_root, u64 owner,
u64 offset, int action, int no_quota)
{
- struct btrfs_delayed_ref_node *existing;
struct btrfs_delayed_data_ref *full_ref;
struct btrfs_delayed_ref_root *delayed_refs;
u64 seq = 0;
+ int ret;
if (action == BTRFS_ADD_DELAYED_EXTENT)
action = BTRFS_ADD_DELAYED_REF;
trace_add_delayed_data_ref(ref, full_ref, action);
- spin_lock(&head_ref->lock);
- existing = tree_insert(&head_ref->ref_root, &ref->rb_node);
- if (existing) {
- update_existing_ref(trans, delayed_refs, head_ref, existing,
- ref);
- /*
- * we've updated the existing ref, free the newly
- * allocated ref
- */
+ ret = add_delayed_ref_tail_merge(trans, delayed_refs, head_ref, ref);
+
+ if (ret > 0)
kmem_cache_free(btrfs_delayed_data_ref_cachep, full_ref);
- } else {
- atomic_inc(&delayed_refs->num_entries);
- trans->delayed_ref_updates++;
- }
- spin_unlock(&head_ref->lock);
}
/*
projects / deliverable / linux.git / blobdiff