From: Qu Wenruo Date: Mon, 30 Mar 2015 09:12:29 +0000 (+0800) Subject: btrfs: delayed-ref: Cleanup the unneeded functions. X-Git-Tag: firefly_0821_release~176^2~1298^2~49 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=c43d160fcd5e4e4f7d2983f5d5253ca33a1596ca;p=firefly-linux-kernel-4.4.55.git btrfs: delayed-ref: Cleanup the unneeded functions. Cleanup the rb_tree merge/insert/update functions, since now we use list instead of rb_tree now. Signed-off-by: Qu Wenruo Signed-off-by: Chris Mason --- diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c index 4dbc31636d14..fc9563d42693 100644 --- a/fs/btrfs/delayed-ref.c +++ b/fs/btrfs/delayed-ref.c @@ -84,87 +84,6 @@ static int comp_data_refs(struct btrfs_delayed_data_ref *ref2, return 0; } -/* - * entries in the rb tree are ordered by the byte number of the extent, - * type of the delayed backrefs and content of delayed backrefs. - */ -static int comp_entry(struct btrfs_delayed_ref_node *ref2, - struct btrfs_delayed_ref_node *ref1, - bool compare_seq) -{ - if (ref1->bytenr < ref2->bytenr) - return -1; - if (ref1->bytenr > ref2->bytenr) - return 1; - if (ref1->is_head && ref2->is_head) - return 0; - if (ref2->is_head) - return -1; - if (ref1->is_head) - return 1; - if (ref1->type < ref2->type) - return -1; - if (ref1->type > ref2->type) - return 1; - if (ref1->no_quota > ref2->no_quota) - return 1; - if (ref1->no_quota < ref2->no_quota) - return -1; - /* merging of sequenced refs is not allowed */ - if (compare_seq) { - if (ref1->seq < ref2->seq) - return -1; - if (ref1->seq > ref2->seq) - return 1; - } - if (ref1->type == BTRFS_TREE_BLOCK_REF_KEY || - ref1->type == BTRFS_SHARED_BLOCK_REF_KEY) { - return comp_tree_refs(btrfs_delayed_node_to_tree_ref(ref2), - btrfs_delayed_node_to_tree_ref(ref1), - ref1->type); - } else if (ref1->type == BTRFS_EXTENT_DATA_REF_KEY || - ref1->type == BTRFS_SHARED_DATA_REF_KEY) { - return comp_data_refs(btrfs_delayed_node_to_data_ref(ref2), - btrfs_delayed_node_to_data_ref(ref1)); - } - BUG(); - return 0; -} - -/* - * insert a new ref into the rbtree. This returns any existing refs - * for the same (bytenr,parent) tuple, or NULL if the new node was properly - * inserted. - */ -static struct btrfs_delayed_ref_node *tree_insert(struct rb_root *root, - struct rb_node *node) -{ - struct rb_node **p = &root->rb_node; - struct rb_node *parent_node = NULL; - struct btrfs_delayed_ref_node *entry; - struct btrfs_delayed_ref_node *ins; - int cmp; - - ins = rb_entry(node, struct btrfs_delayed_ref_node, rb_node); - while (*p) { - parent_node = *p; - entry = rb_entry(parent_node, struct btrfs_delayed_ref_node, - rb_node); - - cmp = comp_entry(entry, ins, 1); - if (cmp < 0) - p = &(*p)->rb_left; - else if (cmp > 0) - p = &(*p)->rb_right; - else - return entry; - } - - rb_link_node(node, parent_node, p); - rb_insert_color(node, root); - return NULL; -} - /* insert a new ref to head ref rbtree */ static struct btrfs_delayed_ref_head *htree_insert(struct rb_root *root, struct rb_node *node) @@ -277,57 +196,6 @@ static inline void drop_delayed_ref(struct btrfs_trans_handle *trans, trans->delayed_ref_updates--; } -static int merge_ref(struct btrfs_trans_handle *trans, - struct btrfs_delayed_ref_root *delayed_refs, - struct btrfs_delayed_ref_head *head, - struct btrfs_delayed_ref_node *ref, u64 seq) -{ - struct rb_node *node; - int mod = 0; - int done = 0; - - node = rb_next(&ref->rb_node); - while (!done && node) { - struct btrfs_delayed_ref_node *next; - - next = rb_entry(node, struct btrfs_delayed_ref_node, rb_node); - node = rb_next(node); - if (seq && next->seq >= seq) - break; - if (comp_entry(ref, next, 0)) - continue; - - if (ref->action == next->action) { - mod = next->ref_mod; - } else { - if (ref->ref_mod < next->ref_mod) { - struct btrfs_delayed_ref_node *tmp; - - tmp = ref; - ref = next; - next = tmp; - done = 1; - } - mod = -next->ref_mod; - } - - drop_delayed_ref(trans, delayed_refs, head, next); - ref->ref_mod += mod; - if (ref->ref_mod == 0) { - drop_delayed_ref(trans, delayed_refs, head, ref); - done = 1; - } else { - /* - * You can't have multiples of the same ref on a tree - * block. - */ - WARN_ON(ref->type == BTRFS_TREE_BLOCK_REF_KEY || - ref->type == BTRFS_SHARED_BLOCK_REF_KEY); - } - } - return done; -} - int btrfs_check_delayed_seq(struct btrfs_fs_info *fs_info, struct btrfs_delayed_ref_root *delayed_refs, u64 seq) @@ -400,48 +268,6 @@ again: return head; } -/* - * helper function to update an extent delayed ref in the - * rbtree. existing and update must both have the same - * bytenr and parent - * - * This may free existing if the update cancels out whatever - * operation it was doing. - */ -static noinline void -update_existing_ref(struct btrfs_trans_handle *trans, - struct btrfs_delayed_ref_root *delayed_refs, - struct btrfs_delayed_ref_head *head, - struct btrfs_delayed_ref_node *existing, - struct btrfs_delayed_ref_node *update) -{ - if (update->action != existing->action) { - /* - * this is effectively undoing either an add or a - * drop. We decrement the ref_mod, and if it goes - * down to zero we just delete the entry without - * every changing the extent allocation tree. - */ - existing->ref_mod--; - if (existing->ref_mod == 0) - drop_delayed_ref(trans, delayed_refs, head, existing); - else - WARN_ON(existing->type == BTRFS_TREE_BLOCK_REF_KEY || - existing->type == BTRFS_SHARED_BLOCK_REF_KEY); - } else { - WARN_ON(existing->type == BTRFS_TREE_BLOCK_REF_KEY || - existing->type == BTRFS_SHARED_BLOCK_REF_KEY); - /* - * the action on the existing ref matches - * the action on the ref we're trying to add. - * Bump the ref_mod by one so the backref that - * is eventually added/removed has the correct - * reference count - */ - existing->ref_mod += update->ref_mod; - } -} - /* * Helper to insert the ref_node to the tail or merge with tail. *