move some locks, nbd

rbf/db.go

@@ -380,6 +380,9 @@ func (db *DB) checkpoint() (err error) {
 
 	db.afterCurrentTx(func() {
 		defer db.rwmu.Unlock()
+		db.baseWALID = readMetaWALID(db.data)
+		db.mu.Unlock()
+		defer db.mu.Lock()
 
 		if err = db.walFile.Truncate(0); err != nil {
 			db.logger.Errorf("truncate wal file: %w", err)
@@ -389,7 +392,6 @@ func (db *DB) checkpoint() (err error) {
 			db.logger.Errorf("seek wal file: %w", err)
 		}
 
-		db.baseWALID = readMetaWALID(db.data)
 	})
 
 	return nil

rbf/tx.go

@@ -102,8 +102,6 @@ func (tx *Tx) Commit() error {
 
 	// If any pages have been written, ensure we write a new meta page with
 	// the commit flag to mark the end of the transaction.
-	tx.db.mu.Lock()
-	defer tx.db.mu.Unlock()
 	if tx.dirty() {
 		if err := tx.flush(); err != nil {
 			return err
@@ -120,11 +118,15 @@ func (tx *Tx) Commit() error {
 		// the lock, because we need removeTx to grab the lock to
 		// work, but if it wants to checkpoint, it wants to be able to return
 		// to us here and still be holding the lock.
+		tx.db.mu.Lock()
 		tx.db.rootRecords = tx.rootRecords
 		tx.db.pageMap = tx.pageMap
 		tx.db.walPageN = tx.walPageN
+		tx.db.mu.Unlock()
 	}
 
+	tx.db.mu.Lock()
+	defer tx.db.mu.Unlock()
 	// Disconnect transaction from DB.
 	return tx.db.removeTx(tx)
 }