Add missing Tx instrumentation

redis.go

@@ -32,10 +32,16 @@ type hooks struct {
 	hooks []Hook
 }
 
-func (hs hooks) Lock() {
+func (hs *hooks) Lock() {
 	hs.hooks = hs.hooks[:len(hs.hooks):len(hs.hooks)]
 }
 
+func (hs hooks) Clone() hooks {
+	clone := hs
+	clone.Lock()
+	return clone
+}
+
 func (hs *hooks) AddHook(hook Hook) {
 	hs.hooks = append(hs.hooks, hook)
 }