bcachefs: Add an assertion to track down a heisenbug

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

diff --git a/fs/bcachefs/btree_update_interior.c b/fs/bcachefs/btree_update_interior.c
index 9e2d72bf06b24a416a08a17582b7efb0dde174e3..c9be0d110c64631a843863de26d43dc9729503d4 100644 (file)
--- a/fs/bcachefs/btree_update_interior.c
+++ b/fs/bcachefs/btree_update_interior.c
@@ -1657,6 +1657,8 @@ void __bch2_foreground_maybe_merge(struct bch_fs *c,
        size_t sib_u64s;
        int ret = 0;
 
+       BUG_ON(!btree_node_locked(iter, level));
+
        closure_init_stack(&cl);
 retry:
        BUG_ON(!btree_node_locked(iter, level));