bcachefs: Kill normalize_read_intent_locks()

Before we had the deadlock cycle detector, we didn't want to be holding
read locks when taking intent locks, because blocking on an intent lock
while holding a read lock was a lock ordering violation that could
cause a deadlock.

With the cycle detector this is no longer an issue, so this code can be
deleted.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

diff --git a/fs/bcachefs/btree_update_leaf.c b/fs/bcachefs/btree_update_leaf.c
index 7b21971fa13db4b2b2f582126f5d2baf09f8aae2..ad46c887185b9ff09f5266382e92ada26d2aa6ab 100644 (file)
--- a/fs/bcachefs/btree_update_leaf.c
+++ b/fs/bcachefs/btree_update_leaf.c
@@ -740,62 +740,6 @@ bch2_trans_commit_write_locked(struct btree_trans *trans,
        return ret;
 }
 
-static inline void path_upgrade_readers(struct btree_trans *trans, struct btree_path *path)
-{
-       unsigned l;
-
-       for (l = 0; l < BTREE_MAX_DEPTH; l++)
-               if (btree_node_read_locked(path, l))
-                       BUG_ON(!bch2_btree_node_upgrade(trans, path, l));
-}
-
-static inline void upgrade_readers(struct btree_trans *trans, struct btree_path *path)
-{
-       struct btree *b = path_l(path)->b;
-       unsigned l;
-
-       do {
-               for (l = 0; l < BTREE_MAX_DEPTH; l++)
-                       if (btree_node_read_locked(path, l))
-                               path_upgrade_readers(trans, path);
-       } while ((path = prev_btree_path(trans, path)) &&
-                path_l(path)->b == b);
-}
-
-/*
- * Check for nodes that we have both read and intent locks on, and upgrade the
- * readers to intent:
- */
-static inline void normalize_read_intent_locks(struct btree_trans *trans)
-{
-       struct btree_path *path;
-       unsigned i, nr_read = 0, nr_intent = 0;
-
-       trans_for_each_path_inorder(trans, path, i) {
-               struct btree_path *next = i + 1 < trans->nr_sorted
-                       ? trans->paths + trans->sorted[i + 1]
-                       : NULL;
-
-               switch (btree_node_locked_type(path, path->level)) {
-               case BTREE_NODE_READ_LOCKED:
-                       nr_read++;
-                       break;
-               case BTREE_NODE_INTENT_LOCKED:
-                       nr_intent++;
-                       break;
-               }
-
-               if (!next || path_l(path)->b != path_l(next)->b) {
-                       if (nr_read && nr_intent)
-                               upgrade_readers(trans, path);
-
-                       nr_read = nr_intent = 0;
-               }
-       }
-
-       bch2_trans_verify_locks(trans);
-}
-
 static inline int trans_lock_write(struct btree_trans *trans)
 {
        struct btree_insert_entry *i;
@@ -899,8 +843,6 @@ static inline int do_bch2_trans_commit(struct btree_trans *trans,
        if (unlikely(ret))
                return ret;
 
-       normalize_read_intent_locks(trans);
-
        ret = trans_lock_write(trans);
        if (unlikely(ret))
                return ret;