打印函数指针指向的函数名：

printk(KERN_ERR "%s: func %pS is at address: %px\n", __func__, hdev->send, hdev->send);

打印当前函数的调用者的函数名：

printk(KERN_ERR "%s: the func's caller is %pS\n", __func__, __builtin_return_address(0));