Yii框架 - 自动执行入口和出口函数调用的记录器

I am writing a application in Yii Framework .Using the Yii Logger for my application log . I want to write log on entry and exit of each function . Now what i have to do is to go in each function and write the entry and exit log . Is there any way in yii from which this entry and exit log would be automatically logged in log file ?

Thanks ,