bcachefs: Btree splits no longer automatically cause a transaction restart

With the new and improved handling of transaction restarts, this should
finally be safe.

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 b119bb9eb6f127aa7fc336dde5b5fa27dc19d814..7ce94340f81767379365982c8e85fb6964134a17 100644 (file)
--- a/fs/bcachefs/btree_update_leaf.c
+++ b/fs/bcachefs/btree_update_leaf.c
@@ -524,14 +524,8 @@ static noinline int maybe_do_btree_merge(struct btree_trans *trans, struct btree
        if (u64s_delta > 0)
                return 0;
 
-       ret = bch2_foreground_maybe_merge(trans, iter, iter->level,
+       return bch2_foreground_maybe_merge(trans, iter, iter->level,
                                trans->flags & ~BTREE_INSERT_NOUNLOCK);
-       if (!ret) {
-               ret = -EINTR;
-               trans->restarted = true;
-       }
-
-       return ret;
 }
 
 /*
@@ -664,50 +658,17 @@ int bch2_trans_commit_error(struct btree_trans *trans,
                            int ret, unsigned long trace_ip)
 {
        struct bch_fs *c = trans->c;
-       unsigned flags = trans->flags;
-
-       /*
-        * BTREE_INSERT_NOUNLOCK means don't unlock _after_ successful btree
-        * update; if we haven't done anything yet it doesn't apply
-        */
-       flags &= ~BTREE_INSERT_NOUNLOCK;
 
        switch (ret) {
        case BTREE_INSERT_BTREE_NODE_FULL:
-               ret = bch2_btree_split_leaf(trans, i->iter, flags);
-
-               /*
-                * if the split succeeded without dropping locks the insert will
-                * still be atomic (what the caller peeked() and is overwriting
-                * won't have changed)
-                */
-#if 0
-               /*
-                * XXX:
-                * split -> btree node merging (of parent node) might still drop
-                * locks when we're not passing it BTREE_INSERT_NOUNLOCK
-                *
-                * we don't want to pass BTREE_INSERT_NOUNLOCK to split as that
-                * will inhibit merging - but we don't have a reliable way yet
-                * (do we?) of checking if we dropped locks in this path
-                */
+               ret = bch2_btree_split_leaf(trans, i->iter, trans->flags);
                if (!ret)
-                       goto retry;
-#endif
+                       return 0;
 
-               /*
-                * don't care if we got ENOSPC because we told split it
-                * couldn't block:
-                */
-               if (!ret ||
-                   ret == -EINTR ||
-                   (flags & BTREE_INSERT_NOUNLOCK)) {
+               if (ret == -EINTR)
                        trace_trans_restart_btree_node_split(trans->ip, trace_ip,
                                                             i->iter->btree_id,
                                                             &i->iter->real_pos);
-                       trans->restarted = true;
-                       ret = -EINTR;
-               }
                break;
        case BTREE_INSERT_NEED_MARK_REPLICAS:
                bch2_trans_unlock(trans);
@@ -764,7 +725,7 @@ int bch2_trans_commit_error(struct btree_trans *trans,
        }
 
        BUG_ON((ret == EINTR || ret == -EAGAIN) && !trans->restarted);
-       BUG_ON(ret == -ENOSPC && (flags & BTREE_INSERT_NOFAIL));
+       BUG_ON(ret == -ENOSPC && (trans->flags & BTREE_INSERT_NOFAIL));
 
        return ret;
 }