How to transfer kernel data to user data using procfs

问题

I am calculating a timestamp in kernel and storing it in a buffer as shown in the code below. I want to make this data available to the user space program by using process file system (procfs). I am finding it very difficult to understand the procfs file system. Can someone help me understand how to do this, or point me in the right direction of some document or tutorial regarding this?

//this code is at network device driver level.
int netif_rx(struct sk_buff *skb) 
{
    __net_timestamp(skb);//I modify the code in kernel to get the timestamp and store in buffer
}

来源：https://stackoverflow.com/questions/23080920/how-to-transfer-kernel-data-to-user-data-using-procfs